The television first (13) ________ about seventy years ago in the 1950s. Since then, it (14) _______ one of the most (15) _______ sources of entertainment for both the old and the young. Television offers cartoons for children, world news, music and many other (16) ________. If someone is interested in sports, for (17) ________, he can just choose the right sport channel. There he can enjoy a broadcast of an international match (18) ________ it is actually happening. Television is also a very useful way for companies to advertise their products. It is not too hard for us (19) ________ why there is a TV set in almost every home today. And engineers are developing interactive TV (20) _________ allows communication between viewers and producers.

Solar energy is a long lasting source of energy which can be used almost anywhere. To generate solar energy, we only need solar cells and the sun. Solar cells can easily be installed on house roofs, so no new space is needed and users can quietly generate their own energy. Compared to other renewable sources, they also possess many advantages. Wind and water power rely on turbines which are noisy, expensive and easy to break down. Solar cells are totally silent and non-polluting. As they have no moving parts, they require little maintenance and have a long lifetime.

However, solar energy also has some disadvantages. We can only generate solar energy during daytime because the system depends on sunlight. Besides, solar cells require large areas to work effectively. The main disadvantage of solar energy is that it costs about twice as much as traditional sources such as coal, oil and gas. This is because solar cells are expensive. Scientists are hoping that the costs of solar cells will reduce as more and more people see the advantages of this environmentally friendly source of energy.

Complete the second sentence so that it has a similar meaning to the first one.

(Hoàn thành câu thứ hai sao cho cùng nghĩa với câu thứ nhất)

They built a supermarket near the airport last year.

=>A supermarket .

Complete the second sentence so that it has a similar meaning to the first one.

(Hoàn thành câu thứ hai sao cho cùng nghĩa với câu thứ nhất)

The boys said "We have to try our best to win the match".

=>  The boys said .

Complete the second sentence so that it has a similar meaning to the first one.

(Hoàn thành câu thứ hai sao cho cùng nghĩa với câu thứ nhất)

 Julia has worked for this company for six years.

=> Julia started .

Complete the second sentence so that it has a similar meaning to the first one.

(Hoàn thành câu thứ hai sao cho cùng nghĩa với câu thứ nhất)

My friend has decided to buy a bicycle. His motorbike was stolen last week.

=>  My friend, whose, .