Bộ đề thi thử 2019 Tiếng Anh cực hay có lời giải chi tiết (Đề số 17)

Mark the letter A, B, C, or D on your answer sheet to indicate the word whose underlined part differs from the other three in pronunciation in each of the following questions.

Mark the letter A, B, C, or D on your answer sheet to indicate the word that differs from the other three in the position of primary stress in each of the following questions.

Mark the letter A, B, C, or D on your answer sheet to indicate the word that differs from the other three in the position of primary stress in each of the following questions.

Mark the letter A, B, C, or D on your answer sheet to indicate the underlined part that needs correction in each of the following questions.

Measles are (A) a very contagious (B) disease that can spread through contact with (C) infected mucus A and (D) saliva.

Mark the letter A, B, C, or D on your answer sheet to indicate the underlined part that needs correction in each of the following questions.

I always (A) forget closing (B) the (C) door before going out.(D)

Mark the letter A, B, C, or D on your answer sheet to indicate the underlined part that needs correction in each of the following questions.

For such (A) a demanding job, you will need qualifications,(B) soft skills and having full (C)

 commitment.(D)

Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions

The last half of the nineteeth century_____a steady improvement in the means of travel.

Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions.

George finally succeeded in swimming across the lake at his fourth______.

Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions.

He was very lucky when he fell off the ladder. He______himself.

Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions.

________her supervisor’s approval, she shouldn’t begin the project.

Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions.

Modem computer science and artificial intelligence_______in the pre-war work of Goedel,

Turing, and Zuse.

Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions.

Students are_______less pressure as a result of changes in testing procedures.

Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions

Tom is getting ever keener on doing research on_______.

Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions.

The most______mineral derived from the sea is sodium chloride or common salt.

Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions.

A number of young teachers nowadays_______themselves to teaching disadvantaged children.

Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions.

Cutting in lines at the grocery store, for example, or being habitually late for meetings is considered  behavior.

Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions.

Sorry for being late. I was_________in the traffic for more than an hour.

Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions.

She was tired and couldn’t keep______the group.

Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions.

Two friends, Diana and Anne, are talking about Anne’s new blouse.

Diana: “That blouse suits you perfectly, Anne.”

Anne: “________.”

Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions.

Mary is talking to a porter in the hotel lobby.

Porter: “Shall I help you with your suitcase?”

Mary: “______”

Mark the letter A, B, c, or D on your answer sheet to indicate the word(s) CLOSEST in meaning to the underlined word(s) in each of the following questions.

Students are expected to always adhere to school regulations.

Mark the letter A, B, c, or D on your answer sheet to indicate the word(s) CLOSEST in meaning to the underlined word(s) in each of the following questions.

A number of programs have been initiated to provide food and shelter for the underprivileged in the remote areas of the country.

Mark the letter A, B, C, or D on your answer sheet to indicate the word(s) OPPOSITE in meaning to the underlined word(s) in each of the following questions.

Drivers are advised to get enough petrol because filling stations are few and far between on the highway.

Mark the letter A, B, C, or D on your answer sheet to indicate the word(s) OPPOSITE in meaning to the underlined word(s) in each of the following questions.

A relaxed and convivial group of around 45 Slow Food members and friends is sharing a simple BBQ lunch.

Mark the letter A, B, C, or D on your answer sheet to indicate the word(s) OPPOSITE in meaning to the underlined word(s) in each of the following questions

I’m sure Luisa was very disappointed when she failed to get the scholarship.

Mark the letter A, B, C, or D on your answer sheet to indicate the word(s) OPPOSITE in meaning to the underlined word(s) in each of the following questions.

“You had better see a doctor if the sore throat does not clear up”, she said to me.

Mark the letter A, B, C, or D on your answer sheet to indicate the word(s) OPPOSITE in meaning to the underlined word(s) in each of the following questions.

Without her teacher’s advice, she would never have written such a good essay.

Mark the letter A, B, C, or D on your answer sheet to indicate the sentence that best combines each pair of sentences in the following questions.

She tried very hard to pass the driving test. She could hardly pass it.

Mark the letter A, B, C, or D on your answer sheet to indicate the sentence that best combines each pair of sentences in the following questions.

We didn’t want to spend a lot of money. We stayed in a cheap hotel.

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks from 31 to 35.

WAYS TO IMPROVE YOUR MEMORY

        A good memory is often seen as something that comes naturally, and a bad memory as something that cannot be changed, but actually there is a lot that you can do to improve your memory.

 We all remember the things we are interested in and forget the ones that bore US. This no doubt explains

the reason (31)______schoolboys remember football results effortlessly but struggle (32)________dates

from their history lessons! Take an active interest in what you want to remember, and focus on it (33)______.One way to make yourself more interested is to ask questions — the more the better!

      Physical exercise is also important for your memory, because it increases your heart (34)_______and

sends more oxygen to your brain, and that makes your memory work better. Exercise also reducesstress, which is very bad for the memory.

      The old saying that —eating fish makes you brainyl may be true after all. Scientists have discovered

that the fats (35)_______in fish like tuna, sardines and salmon — as well as in olive oil - help to improve the memory. Vitamin-rich fruits such as oranges, strawberries and red grapes are all good - brain food, too.

(Source: —New Cutting Edge, Cunningham, S. & Moor. 2010. Harlow: Longman)

Điền vào số 31

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks from 31 to 35.

WAYS TO IMPROVE YOUR MEMORY

        A good memory is often seen as something that comes naturally, and a bad memory as something that cannot be changed, but actually there is a lot that you can do to improve your memory.

 We all remember the things we are interested in and forget the ones that bore US. This no doubt explains

the reason (31)______schoolboys remember football results effortlessly but struggle (32)________dates

from their history lessons! Take an active interest in what you want to remember, and focus on it (33)______.One way to make yourself more interested is to ask questions — the more the better!

      Physical exercise is also important for your memory, because it increases your heart (34)_______and

sends more oxygen to your brain, and that makes your memory work better. Exercise also reducesstress, which is very bad for the memory.

      The old saying that —eating fish makes you brainyl may be true after all. Scientists have discovered

that the fats (35)_______in fish like tuna, sardines and salmon — as well as in olive oil - help to improve the memory. Vitamin-rich fruits such as oranges, strawberries and red grapes are all good - brain food, too.

(Source: —New Cutting Edge, Cunningham, S. & Moor. 2010. Harlow: Longman)

Điền vào số 32

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks from 31 to 35.

WAYS TO IMPROVE YOUR MEMORY

        A good memory is often seen as something that comes naturally, and a bad memory as something that cannot be changed, but actually there is a lot that you can do to improve your memory.

 We all remember the things we are interested in and forget the ones that bore US. This no doubt explains

the reason (31)______schoolboys remember football results effortlessly but struggle (32)________dates

from their history lessons! Take an active interest in what you want to remember, and focus on it (33)______.One way to make yourself more interested is to ask questions — the more the better!

      Physical exercise is also important for your memory, because it increases your heart (34)_______and

sends more oxygen to your brain, and that makes your memory work better. Exercise also reducesstress, which is very bad for the memory.

      The old saying that —eating fish makes you brainyl may be true after all. Scientists have discovered

that the fats (35)_______in fish like tuna, sardines and salmon — as well as in olive oil - help to improve the memory. Vitamin-rich fruits such as oranges, strawberries and red grapes are all good - brain food, too.

(Source: —New Cutting Edge, Cunningham, S. & Moor. 2010. Harlow: Longman)

Điền vào số 33

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks from 31 to 35.

WAYS TO IMPROVE YOUR MEMORY

        A good memory is often seen as something that comes naturally, and a bad memory as something that cannot be changed, but actually there is a lot that you can do to improve your memory.

 We all remember the things we are interested in and forget the ones that bore US. This no doubt explains

the reason (31)______schoolboys remember football results effortlessly but struggle (32)________dates

from their history lessons! Take an active interest in what you want to remember, and focus on it (33)______.One way to make yourself more interested is to ask questions — the more the better!

      Physical exercise is also important for your memory, because it increases your heart (34)_______and

sends more oxygen to your brain, and that makes your memory work better. Exercise also reducesstress, which is very bad for the memory.

      The old saying that —eating fish makes you brainyl may be true after all. Scientists have discovered

that the fats (35)_______in fish like tuna, sardines and salmon — as well as in olive oil - help to improve the memory. Vitamin-rich fruits such as oranges, strawberries and red grapes are all good - brain food, too.

(Source: —New Cutting Edge, Cunningham, S. & Moor. 2010. Harlow: Longman)

Điền vào số 34

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks from 31 to 35.

WAYS TO IMPROVE YOUR MEMORY

        A good memory is often seen as something that comes naturally, and a bad memory as something that cannot be changed, but actually there is a lot that you can do to improve your memory.

 We all remember the things we are interested in and forget the ones that bore US. This no doubt explains

the reason (31)______schoolboys remember football results effortlessly but struggle (32)________dates

from their history lessons! Take an active interest in what you want to remember, and focus on it (33)______.One way to make yourself more interested is to ask questions — the more the better!

      Physical exercise is also important for your memory, because it increases your heart (34)_______and

sends more oxygen to your brain, and that makes your memory work better. Exercise also reducesstress, which is very bad for the memory.

      The old saying that —eating fish makes you brainyl may be true after all. Scientists have discovered

that the fats (35)_______in fish like tuna, sardines and salmon — as well as in olive oil - help to improve the memory. Vitamin-rich fruits such as oranges, strawberries and red grapes are all good - brain food, too.

(Source: —New Cutting Edge, Cunningham, S. & Moor. 2010. Harlow: Longman)

Điền vào số 35

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 36 to 42.

          Martin Luther King, Jf, is well- known for his work in civil rights and for his many famous speeches, among which is his moving “I have a dream” speech. But fewer people know much about King’s childhooD. M.L., as he was called, was bom in 1929 in Atlanta, Georgia, at the home of his maternal grandfather. M.L.’s grandfather purchased their home on Auburn Avenue in 1909, twenty years before M.L was bom. His grandfather allowed the house to be used as a meeting place for a number of organizations dedicated to the education and social advancement of blacks. M.L. grew up in the atmosphere, with his home being used as a community gathering place, and was no doubt influenced by it.

M.L.’s childhood was not especially eventfully. His father was a minister and his mother was a musician. He was the second of three children, and he attended all black schools in a black neighborhood. The neighborhood was not poor, however. Auburn Avenue was an area of banks, insurance companies, builders, jewelers, tailors, doctors, lawyers, and other businesses and services. Even in the face of Atlanta’s segregation, the district thrived. Dr. King never forgot the community spirit he had known as a child, nor did he forget the racial prejudice that was a huge barrier keeping black Atlantans from mingling with whites.

What is the passage mainly about?

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 36 to 42.

          Martin Luther King, Jf, is well- known for his work in civil rights and for his many famous speeches, among which is his moving “I have a dream” speech. But fewer people know much about King’s childhooD. M.L., as he was called, was bom in 1929 in Atlanta, Georgia, at the home of his maternal grandfather. M.L.’s grandfather purchased their home on Auburn Avenue in 1909, twenty years before M.L was bom. His grandfather allowed the house to be used as a meeting place for a number of organizations dedicated to the education and social advancement of blacks. M.L. grew up in the atmosphere, with his home being used as a community gathering place, and was no doubt influenced by it.

M.L.’s childhood was not especially eventfully. His father was a minister and his mother was a musician. He was the second of three children, and he attended all black schools in a black neighborhood. The neighborhood was not poor, however. Auburn Avenue was an area of banks, insurance companies, builders, jewelers, tailors, doctors, lawyers, and other businesses and services. Even in the face of Atlanta’s segregation, the district thrived. Dr. King never forgot the community spirit he had known as a child, nor did he forget the racial prejudice that was a huge barrier keeping black Atlantans from mingling with whites.

When was M.L. bom?

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 36 to 42.

          Martin Luther King, Jf, is well- known for his work in civil rights and for his many famous speeches, among which is his moving “I have a dream” speech. But fewer people know much about King’s childhooD. M.L., as he was called, was bom in 1929 in Atlanta, Georgia, at the home of his maternal grandfather. M.L.’s grandfather purchased their home on Auburn Avenue in 1909, twenty years before M.L was bom. His grandfather allowed the house to be used as a meeting place for a number of organizations dedicated to the education and social advancement of blacks. M.L. grew up in the atmosphere, with his home being used as a community gathering place, and was no doubt influenced by it.

M.L.’s childhood was not especially eventfully. His father was a minister and his mother was a musician. He was the second of three children, and he attended all black schools in a black neighborhood. The neighborhood was not poor, however. Auburn Avenue was an area of banks, insurance companies, builders, jewelers, tailors, doctors, lawyers, and other businesses and services. Even in the face of Atlanta’s segregation, the district thrived. Dr. King never forgot the community spirit he had known as a child, nor did he forget the racial prejudice that was a huge barrier keeping black Atlantans from mingling with whites.

What is Martin Luthur King well- known for?

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 36 to 42.

          Martin Luther King, Jf, is well- known for his work in civil rights and for his many famous speeches, among which is his moving “I have a dream” speech. But fewer people know much about King’s childhooD. M.L., as he was called, was bom in 1929 in Atlanta, Georgia, at the home of his maternal grandfather. M.L.’s grandfather purchased their home on Auburn Avenue in 1909, twenty years before M.L was bom. His grandfather allowed the house to be used as a meeting place for a number of organizations dedicated to the education and social advancement of blacks. M.L. grew up in the atmosphere, with his home being used as a community gathering place, and was no doubt influenced by it.

M.L.’s childhood was not especially eventfully. His father was a minister and his mother was a musician. He was the second of three children, and he attended all black schools in a black neighborhood. The neighborhood was not poor, however. Auburn Avenue was an area of banks, insurance companies, builders, jewelers, tailors, doctors, lawyers, and other businesses and services. Even in the face of Atlanta’s segregation, the district thrived. Dr. King never forgot the community spirit he had known as a child, nor did he forget the racial prejudice that was a huge barrier keeping black Atlantans from mingling with whites.

According to the author, M.L.________.

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 36 to 42.

          Martin Luther King, Jf, is well- known for his work in civil rights and for his many famous speeches, among which is his moving “I have a dream” speech. But fewer people know much about King’s childhooD. M.L., as he was called, was bom in 1929 in Atlanta, Georgia, at the home of his maternal grandfather. M.L.’s grandfather purchased their home on Auburn Avenue in 1909, twenty years before M.L was bom. His grandfather allowed the house to be used as a meeting place for a number of organizations dedicated to the education and social advancement of blacks. M.L. grew up in the atmosphere, with his home being used as a community gathering place, and was no doubt influenced by it.

M.L.’s childhood was not especially eventfully. His father was a minister and his mother was a musician. He was the second of three children, and he attended all black schools in a black neighborhood. The neighborhood was not poor, however. Auburn Avenue was an area of banks, insurance companies, builders, jewelers, tailors, doctors, lawyers, and other businesses and services. Even in the face of Atlanta’s segregation, the district thrived. Dr. King never forgot the community spirit he had known as a child, nor did he forget the racial prejudice that was a huge barrier keeping black Atlantans from mingling with whites. 

Which of the following statements is NOT true?

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 36 to 42.

          Martin Luther King, Jf, is well- known for his work in civil rights and for his many famous speeches, among which is his moving “I have a dream” speech. But fewer people know much about King’s childhooD. M.L., as he was called, was bom in 1929 in Atlanta, Georgia, at the home of his maternal grandfather. M.L.’s grandfather purchased their home on Auburn Avenue in 1909, twenty years before M.L was bom. His grandfather allowed the house to be used as a meeting place for a number of organizations dedicated to the education and social advancement of blacks. M.L. grew up in the atmosphere, with his home being used as a community gathering place, and was no doubt influenced by it.

M.L.’s childhood was not especially eventfully. His father was a minister and his mother was a musician. He was the second of three children, and he attended all black schools in a black neighborhood. The neighborhood was not poor, however. Auburn Avenue was an area of banks, insurance companies, builders, jewelers, tailors, doctors, lawyers, and other businesses and services. Even in the face of Atlanta’s segregation, the district thrived. Dr. King never forgot the community spirit he had known as a child, nor did he forget the racial prejudice that was a huge barrier keeping black Atlantans from mingling with whites.

From the passage we can infer that______.

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 36 to 42.

          Martin Luther King, Jf, is well- known for his work in civil rights and for his many famous speeches, among which is his moving “I have a dream” speech. But fewer people know much about King’s childhooD. M.L., as he was called, was bom in 1929 in Atlanta, Georgia, at the home of his maternal grandfather. M.L.’s grandfather purchased their home on Auburn Avenue in 1909, twenty years before M.L was bom. His grandfather allowed the house to be used as a meeting place for a number of organizations dedicated to the education and social advancement of blacks. M.L. grew up in the atmosphere, with his home being used as a community gathering place, and was no doubt influenced by it.

M.L.’s childhood was not especially eventfully. His father was a minister and his mother was a musician. He was the second of three children, and he attended all black schools in a black neighborhood. The neighborhood was not poor, however. Auburn Avenue was an area of banks, insurance companies, builders, jewelers, tailors, doctors, lawyers, and other businesses and services. Even in the face of Atlanta’s segregation, the district thrived. Dr. King never forgot the community spirit he had known as a child, nor did he forget the racial prejudice that was a huge barrier keeping black Atlantans from mingling with whites.

M.L. was________by the atmosphere in which he grew up.

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 43 to 50.

         Carbon dating can be used to estimate the age of any organic natural material; it has been used successfully in archeology to determine the age of ancient artifacts or fossils as well as in a variety of other fields. The principle underlying the use of carbon dating is that carbon is a part of all living things on Earth. Since a radioactive substance such as carbon-14 has a known half-life, the amount of carbon-14 remaining in an object can be used to date that object.

        Carbon-14 has a half-life of 5,570 years, which means that after that number of years, half of the carbon- 14 atoms have decayed into nitrogen-14. It is the ratio of carbon-14 in that substance that indicates the age of the substance. If, for example, in a particular sample the amount of carbon-14 is roughly equivalent to the amount of nitrogen-14, this indicates that around half of the carbon-14 has decayed into nitrogen-14, and the sample is approximately 5,570 years old.

        Carbon dating cannot be used effectively in dating objects that are older than 80,000 years. When objects are that old, much of the carbon-14 has already decayed into nitrogen-14, and the miniscule amount that is left doesn’t provide a reliable measurement of age. In the case of older objects, other age-dating methods are available, methods which use radioactive atoms with longer half-lives than carbon has.

This passage is mainly about ______.

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 43 to 50.

         Carbon dating can be used to estimate the age of any organic natural material; it has been used successfully in archeology to determine the age of ancient artifacts or fossils as well as in a variety of other fields. The principle underlying the use of carbon dating is that carbon is a part of all living things on Earth. Since a radioactive substance such as carbon-14 has a known half-life, the amount of carbon-14 remaining in an object can be used to date that object.

        Carbon-14 has a half-life of 5,570 years, which means that after that number of years, half of the carbon- 14 atoms have decayed into nitrogen-14. It is the ratio of carbon-14 in that substance that indicates the age of the substance. If, for example, in a particular sample the amount of carbon-14 is roughly equivalent to the amount of nitrogen-14, this indicates that around half of the carbon-14 has decayed into nitrogen-14, and the sample is approximately 5,570 years old.

        Carbon dating cannot be used effectively in dating objects that are older than 80,000 years. When objects are that old, much of the carbon-14 has already decayed into nitrogen-14, and the miniscule amount that is left doesn’t provide a reliable measurement of age. In the case of older objects, other age-dating methods are available, methods which use radioactive atoms with longer half-lives than carbon has.

Which of the following is NOT true about carbon-14?

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 43 to 50.

         Carbon dating can be used to estimate the age of any organic natural material; it has been used successfully in archeology to determine the age of ancient artifacts or fossils as well as in a variety of other fields. The principle underlying the use of carbon dating is that carbon is a part of all living things on Earth. Since a radioactive substance such as carbon-14 has a known half-life, the amount of carbon-14 remaining in an object can be used to date that object.

        Carbon-14 has a half-life of 5,570 years, which means that after that number of years, half of the carbon- 14 atoms have decayed into nitrogen-14. It is the ratio of carbon-14 in that substance that indicates the age of the substance. If, for example, in a particular sample the amount of carbon-14 is roughly equivalent to the amount of nitrogen-14, this indicates that around half of the carbon-14 has decayed into nitrogen-14, and the sample is approximately 5,570 years old.

        Carbon dating cannot be used effectively in dating objects that are older than 80,000 years. When objects are that old, much of the carbon-14 has already decayed into nitrogen-14, and the miniscule amount that is left doesn’t provide a reliable measurement of age. In the case of older objects, other age-dating methods are available, methods which use radioactive atoms with longer half-lives than carbon has.

The word “it” in paragraph I refers to________.

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 43 to 50.

         Carbon dating can be used to estimate the age of any organic natural material; it has been used successfully in archeology to determine the age of ancient artifacts or fossils as well as in a variety of other fields. The principle underlying the use of carbon dating is that carbon is a part of all living things on Earth. Since a radioactive substance such as carbon-14 has a known half-life, the amount of carbon-14 remaining in an object can be used to date that object.

        Carbon-14 has a half-life of 5,570 years, which means that after that number of years, half of the carbon- 14 atoms have decayed into nitrogen-14. It is the ratio of carbon-14 in that substance that indicates the age of the substance. If, for example, in a particular sample the amount of carbon-14 is roughly equivalent to the amount of nitrogen-14, this indicates that around half of the carbon-14 has decayed into nitrogen-14, and the sample is approximately 5,570 years old.

        Carbon dating cannot be used effectively in dating objects that are older than 80,000 years. When objects are that old, much of the carbon-14 has already decayed into nitrogen-14, and the miniscule amount that is left doesn’t provide a reliable measurement of age. In the case of older objects, other age-dating methods are available, methods which use radioactive atoms with longer half-lives than carbon has.

The word “underlying” in paragraph I could best be replaced by _______.

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 43 to 50.

         Carbon dating can be used to estimate the age of any organic natural material; it has been used successfully in archeology to determine the age of ancient artifacts or fossils as well as in a variety of other fields. The principle underlying the use of carbon dating is that carbon is a part of all living things on Earth. Since a radioactive substance such as carbon-14 has a known half-life, the amount of carbon-14 remaining in an object can be used to date that object.

        Carbon-14 has a half-life of 5,570 years, which means that after that number of years, half of the carbon- 14 atoms have decayed into nitrogen-14. It is the ratio of carbon-14 in that substance that indicates the age of the substance. If, for example, in a particular sample the amount of carbon-14 is roughly equivalent to the amount of nitrogen-14, this indicates that around half of the carbon-14 has decayed into nitrogen-14, and the sample is approximately 5,570 years old.

        Carbon dating cannot be used effectively in dating objects that are older than 80,000 years. When objects are that old, much of the carbon-14 has already decayed into nitrogen-14, and the miniscule amount that is left doesn’t provide a reliable measurement of age. In the case of older objects, other age-dating methods are available, methods which use radioactive atoms with longer half-lives than carbon has.

The word “roughly” in paragraph 2 is closest in meaning to________.

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 43 to 50.

         Carbon dating can be used to estimate the age of any organic natural material; it has been used successfully in archeology to determine the age of ancient artifacts or fossils as well as in a variety of other fields. The principle underlying the use of carbon dating is that carbon is a part of all living things on Earth. Since a radioactive substance such as carbon-14 has a known half-life, the amount of carbon-14 remaining in an object can be used to date that object.

        Carbon-14 has a half-life of 5,570 years, which means that after that number of years, half of the carbon- 14 atoms have decayed into nitrogen-14. It is the ratio of carbon-14 in that substance that indicates the age of the substance. If, for example, in a particular sample the amount of carbon-14 is roughly equivalent to the amount of nitrogen-14, this indicates that around half of the carbon-14 has decayed into nitrogen-14, and the sample is approximately 5,570 years old.

        Carbon dating cannot be used effectively in dating objects that are older than 80,000 years. When objects are that old, much of the carbon-14 has already decayed into nitrogen-14, and the miniscule amount that is left doesn’t provide a reliable measurement of age. In the case of older objects, other age-dating methods are available, methods which use radioactive atoms with longer half-lives than carbon has.

The paragraph following the passage most probably discusses_____.

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 43 to 50.

         Carbon dating can be used to estimate the age of any organic natural material; it has been used successfully in archeology to determine the age of ancient artifacts or fossils as well as in a variety of other fields. The principle underlying the use of carbon dating is that carbon is a part of all living things on Earth. Since a radioactive substance such as carbon-14 has a known half-life, the amount of carbon-14 remaining in an object can be used to date that object.

        Carbon-14 has a half-life of 5,570 years, which means that after that number of years, half of the carbon- 14 atoms have decayed into nitrogen-14. It is the ratio of carbon-14 in that substance that indicates the age of the substance. If, for example, in a particular sample the amount of carbon-14 is roughly equivalent to the amount of nitrogen-14, this indicates that around half of the carbon-14 has decayed into nitrogen-14, and the sample is approximately 5,570 years old.

        Carbon dating cannot be used effectively in dating objects that are older than 80,000 years. When objects are that old, much of the carbon-14 has already decayed into nitrogen-14, and the miniscule amount that is left doesn’t provide a reliable measurement of age. In the case of older objects, other age-dating methods are available, methods which use radioactive atoms with longer half-lives than carbon has.

It is implied in the passage that .

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 43 to 50.

         Carbon dating can be used to estimate the age of any organic natural material; it has been used successfully in archeology to determine the age of ancient artifacts or fossils as well as in a variety of other fields. The principle underlying the use of carbon dating is that carbon is a part of all living things on Earth. Since a radioactive substance such as carbon-14 has a known half-life, the amount of carbon-14 remaining in an object can be used to date that object.

        Carbon-14 has a half-life of 5,570 years, which means that after that number of years, half of the carbon- 14 atoms have decayed into nitrogen-14. It is the ratio of carbon-14 in that substance that indicates the age of the substance. If, for example, in a particular sample the amount of carbon-14 is roughly equivalent to the amount of nitrogen-14, this indicates that around half of the carbon-14 has decayed into nitrogen-14, and the sample is approximately 5,570 years old.

        Carbon dating cannot be used effectively in dating objects that are older than 80,000 years. When objects are that old, much of the carbon-14 has already decayed into nitrogen-14, and the miniscule amount that is left doesn’t provide a reliable measurement of age. In the case of older objects, other age-dating methods are available, methods which use radioactive atoms with longer half-lives than carbon has.

It can be inferred from the passage that if an item contains more carbon-14 than nitrogen-14, then the item is _______.