问题 填空题

在下面(1)~(4)事实后的空格内,选择填写其所体现的分子基本特征的序号.

A.分子很小B.分子间有间隔

C.分子在不停运动D.同种分子性质相同,不同种分子性质不同

(1)将50mL酒精和50mL水混合后,混合液体积小于100mL.______

(2)湿衣服经晾晒一段时间后,会变干.______

(3)双氧水与二氧化锰混合可以产生氧气,水与二氧化锰混合不可以产生氧气.______

(4)一滴水里的水分子个数如果由10亿人数,每人每分钟数100个,日夜不停地数,也需用3万年才能数完.______.

答案

(1)将50mL水和50mL酒精混合,混合后的体积小于100mL,说明分子之间有间隔;

(2)湿衣服晒一段时间后会变干说明分子是不断运动的;

(3)双氧水可以产生氧气,而水不能和二氧化锰产生氧气,说明不同物质的分子性质不同;

(3)一滴水里的水分子个数由10亿人数,每人每分钟数100个,日夜不停,需3万年才能数完,说明分子很小;

故答案为:

(1)B

(2)C

(3)D

(4)A

选择题
完形填空

II.Fill in the blanks(10)

The first and smallest unit that can be discussed in relation to language is the word. In speaking, the choice of words is   16   great importance. Proper _17__(choose) will get rid of one source of likely breakdown in the communication cycle. Too often, careless use of words___18___ (prevent) a meeting of the mind of the speaker and listener. The words used by the speaker may cause __19___(favor) reactions in the listener_20__interfere with his comprehension; hence, the transmission-reception system breaks down. Moreover , inaccurate or indefinite words may make _21__ difficult for the listener to understand the message which __22__(transmit) to him. The speaker_23__does not have specific words in working vocabulary may be unabe to explain or describe in _24_ way ___25_ can be understood by listeners.

III.cloze(15)

Nobody wants to appear fat. Many girls who care too much about their self-image(个人形象) choose to eat less food to  26   themselves from gaining weight. Some even take medicine to achieve their goals. Those unhealthy ways may lead to being   27  to a certain drug and the addiction is usually very   28  . There is little difference to committing suicide (自杀). I used to eat   29    a lot, which is said to be high in protein but low in calories. But the moment bird flu   30   out, I stopped eating this kind of meat. To me, health always comes first, because no matter how wealthy you are, your   31   will deprive(剥夺) you of the right to   32   your life, so why should we put ourselves in danger and suffer? However, you’d better keep it in mind that whether you go on a calorie-restricted (限制热量的) diet or not, exercising and   33   eating are excellent ways to keep your body in good   34. Their emphasis is that the healthy way to lose weight is   35   to make permanent changes to your lifestyle.

26. A. protect                     B. make                      C. promise                  D. keep

27. A. used               B. addicted             C. exposed             D. devoted

28. A. painful        B. useful             C. cheerful              D. sorrowful

29. A. fruit           B. vegetable           C. chicken              D. pork

30. A. let             B. set                C. gave                 D. broke

31. A. medicine             B. weight             C. diet                 D. disease

32. A. enjoy          B. make             C. change                D. take

33. A. regular        B. healthy            C. good                 D. normal

34. A. size            B. shape              C. situation             D. style

35. A. usually                B. generally          C. quickly                D. gradually