[单项选择]Scientists have been trying to come up with biological explanations for the difference between boys and girls.


A. 科学家们已经努力提出用生物学来解释男孩与女孩间的这种并异。
B. 科学家们已经试图把男生与女生之间的差异用生物来解释。
C. 科学们一直试图从生物学的角度来解释男孩和女孩间的差异。
D. 科学家们已经试图提出男孩和女孩生理上的差异。

[单项选择]So far every means（）tried, but we have not come up with a solution to the problem.
A. is
B. has been
C. are
D. have been

[单项选择]Several tents have been put up to ______the party.

[单项选择]______ have come up with the solutions to the problem.
A. The boy student
B. The boys student
C. The boy students
D. The boys students

[单项选择]Scientists are trying to make（）investigation.
A. further
B. farther
C. furthest
D. farthest

[单项选择]He didn't live up to（）have been expected of him.
A. which
B. what
C. that
D. all what

[单项选择]Scientists are working hard to come up with a sure solution to the food （　）for mankind.
A. decline
B. rarity
C. scarcity
D. shortage

[单项选择]It took a lot of imagination to come up with such an ______ plan.


A. bright
B. clever
C. brilliant
D. ingenious

[单项选择]I have to come to discuss with you about the measures we shall take to cope with the situation．


A. 我得来和你讨论关于我们如何应付这个形势。
B. 我得就目前所发生的事来和你讨论计划。
C. 我得开始和你讨论关于面临这种情况如何掌握分寸。
D. 我得来和你商量一下采取什么措施应付这个局面。

[单项选择]I have been trying to quit smoking.
A. give up
B. pick up
C. build up
D. take up

[单项选择]The plant products have been carefully inspected and are considered to be ( ) from any quarantine pests.
A. out
B. away
C. free
D. far

[单项选择]Americans have been criticized for placing too much （　） on being on time.
A. emphasis
B. activity
C. bother
D. assistance

[单项选择]Major manufacturers have been using "quality circle" with undeniable success for more them two decades.
A. 100 years
B. 20 years
C. 50 years
D. 10 years

[单项选择]The selection says that spiders have been discovered ______.
A. five miles above earth
B. more than 2000 feet underground
C. everywhere that man has reached
D. both A and B

[单项选择]What actions have been take by the government

[单项选择]Their relationships with their parents have been so ______ that they are no longer able to communicate.


A. restless
B. distant
C. tight
D. strained

[单项选择]It took him a lot of imagination to come up with such an ______ plan, a man with less intelligence wouldn't have done so.
A. artful
B. inevitable
C. optimistic
D. ingenious

[单项选择]

Man has been storing up useful knowledge about himself and the universe at the rate which has been spiraling upward for 10,000 years.
　　The (21) took a sharp upward leap with the invention of writing, but even (22) it remained painfully slow for several centuries. The next great leap forward (23) knowledge acquisition did not occur (24) the invention of movable type in the 15th century by Gutenberg and others. (25) to 1500, by the most optimistic (26) Europe was producing books at a rate of 1000 titles per year. This means that it (27) a full century to produce a library of 100,000 titles. By 1950, four and a half (28) later, the rate had accelerated so sharply that Europe was producing 120,000 titles a year. (29) once took a century now took only ten months. By 1960, a (30) decade later, the rate had made another significant jump, (31) a century’s work could be finished in seven and a hal
A. examples
B. estimates
C. evidence
D. evaluation