[单项选择]An inventor can generally make a big profit if he ______ his or her invention.


A. publishes
B. keeps secret
C. patents
D. sells

[单项选择]An inventor can generally make a big profit if he _________ his or her invention.
A. publishes
B. keeps secret
C. patents
D. sells

[单项选择]Who can make big money in the new century according to the passage
A. Retirees who are business-minded.
B. The volunteer workers in retirement homes.
C. College graduates with an MBA or law degree.
D. Professionals with a good knowledge of gerontology.

[单项选择]It doesn't make much difference whether he can finish this work．
A. 他是否能完成这项工作，这已没有什么差异。
B. 他是否能完成这项工作，这关系不大。
C. 他也许能完成这项工作，也许不能，但这无太大的关系。
D. 他完成这项工作就好，完不成这项工作就影响大了。

[单项选择]

Man has a big brain. He can think, learn and speak. Scientists used to think that man are different from animals because they can think and learn. They know now that animals--dogs, rats and birds--can learn. So scientists are beginning to understand that men are different from animals because they can speak. Animals cannot speak. They make noises when they are afraid, or hungry. or unhappy. Apes are our nearest cousins. They can understand some things mole quickly than human beings, and one or two have learned a few words. But they are still different from us. They cannot join words and make sentences. They cannot think like us because they have no language. They can never think about the past or the future. Language is a wonderful thing. Man has been able to develop civilization because he has language. Every child can. speak his own language vet well when he is four or five--but no animal learns to speak. How do children learn Scientists do not really know. What happens when w
A. animals cannot speak
B. animals cannot learn
C. animals cannot think like us
D. animals do not have their own language