Give the correct form of the words in brackets.

The Origin of Language

Over the centuries, language has………..(1. ABLE) humans to share complex

information. This………..(2. WONDER) ability eventually gave us the power to dominate the world. Imagine if people couldn't pass on certain types of information, such as what is required for building a wheel, without having to………..(3. LABOUR) demonstrate the technique. The concept might even die out and have to be re-invented by each new generation. With language, the concept of a wheel can spread very fast, and the original idea can be………..(4. MODIFICATION) and improved on, time and again, until people are able to develop wheels with tyres and spokes. Nobody knows how the human ability to use language………..(5. ORIGIN). There are many different yet interesting theories. Some linguists think it came about because of people's need to ………..(6. OPERATE) with each other in order to hunt large animals. A group of humans communicating with each other would have a better chance of killing a large, ………..(7. POTENTIAL) dangerous animal such as mammoth. Other linguists believe that language stems from a……….. (8. DESIRABLE) to manipulate and control people. They see it as a re-enforcement of physical gesture. And others again attribute speech to the same spark of………..(9. CREATE) that caused our distant ancestors to draw animals on cave walls. Most linguists, however, now believe that it is an ……….. (10. INNATELY) ability, a natural result of the development of the human brain, much like the spider's natural ability to spin webs or the dolphin’s ability to use high-pitched sounds to judge distances.

It's Jack’s…………..that drives his parents crazy. They can't even persuade him to brush his teeth in the morning. (OBSTINATE)