one of the most important discoveries of the nineteenth century was a method of using natural gas for cooking and heating. Large amounts of natural gas found in the United States, usually several thousand feet below the surface of the earth. Natural gas is most found in places where petroleum, the oil from which gasoline is made, is found. Often the natural gas must be removed before the oil itself is reached. For many years after natural gas first discovered, it was thought to have no value. Finally, however, people began to understand its uses and to find ways of storing it and of moving it from place to place. Today natural gas is stored in large tanks and used for lighting, cooking, and heating. In many ways natural gas is one of our finest fuels. It can be used for cooking without making the room hot. It is cheap and can be moved easily from one place to another through long pipelines, some of which are hundreds of miles in length.

Question 33. This passage as a whole is about.......

A. discovering natural gas B. finding petroleum C. using natural gas and petroleum D. natural gas and its use

Question 34. Which of the following is NOT true about natural gas?

A. It is not used for heating. B. It moves through pipes.

 C. It is cheap. D. It can be stored.

Question 35. How many uses of natural gas are mentioned?

D. five A. two B. three C. four

Question 36. What does the word "it" in the passage refer to?

A. natural gas B. electric generator C. pipeline

Question 37. Which of the following is closest meaning to "discovered"?

D. tank A. invented B. found C. used D. stored