Every day we go to school and listen to the teacher, and the teacher will ask us some questions. Sometimes, the classmates will ask for your opinions of the work of the class. When you are telling others in the class what you have found out about these topics, remember that they must be able to hear what you are saying. You are not taking part in a family conversation or having a chat with friends— they will remain silent, waiting to hear what you have to say. In the class, you must speak so that they can hear you—loudly enough and clearly enough but without trying to shout or appearing to force yourself. Remember, too, that it is the same if you are called to an interview whether it is with a professor of your school or a government official who might meet you. The person you are seeing will try to put you at your ease (not worried) but the situation is somewhat different from that of an ordinary conversation. You must take special care that you can be heard. 41. Usually, when you speak to the class, the class is____________. 16．noisy   B. quiet    C. having a rest    D. serious 42. The situation in the class is _____than in your house. A.not very different from   B. sometimes the same as C. sometimes not different from  D. not the same as 43. If you are having a conversation with an official, the most important thing for you     is _________. A. to show your ability              B. to be very gentle C. to make sure that you can be heard  D. to put the official at ease 44. The main idea of the passage is _________. A.that we should not talk in different ways in different situations 17．that we must speak loudly to make ourselves heard when stating our opinions in serious situations 18．that we must keep silent at any time 19．that we must talk with the class