题目内容：

完形填空

阅读下面短文，从短文后所给的四个选项（A、B、C和D）中，选出可以填入空白处的最佳选项。

Washoe is a young chimpanzee. She is no ____1____ chimpanzee, though. Scientists are doing a research ____2____ her. They want to see how civilized (驯化) she can _____3___. Already she does many things a human being can do.

For example, she has been learning how to exchange __4______ with people. The scientists are teaching her ___5_____ language. When she wants to be picked ___6_____, Washoe points up with one finger. She rubs her teeth with her finger ___7_____ she wants to brush her teeth. This is done after every meal.

Washoe has also been __8______ to think out and find answers to problems. Once she was put in a ___9_____ with food hanging from the ceiling. It was too high to ___10_____. After she considered the ____11____, she got a tall box to stand ___12_____. The food was still too high to be reached. Washoe found a ____13____ pole. Then she climbed onto the _____14___, grasped the pole, and _____15___ down the food with the pole. Washoe_____16___ like a human, too. The scientists keep her in a fully furnished house. After a hard ___17_____ in the laboratory, she goes home. ___18_____ she plays with her toys. She ___19_____ enjoys watching television before going to bed. Scientists hope to____20____ more about people by studying our closest relative — chimpanzee.

1.A.foolish B.ordinary C.special D.simple

2.A.for B.by C.to D.on

3.A.experience B.change C.develop D.become

4.A.actions B.views C.messages D.feelings

5.A.sign B.human C.spoken D.foreign

6.A.out B.at C.on D.up

7.A.when B.until C.since D.while

8.A.raised B.trained C.ordered D.led

9.A.cave B.zoo C.room D.museum

10.A.pull B.see C.eat D.reach

11.A.problem B.position C.food D.ceiling

12.A.by B.on C.up D.with

13.A.straight B.strong C.long D.big

14.A.wall B.box C.ceiling D.pole

15.A.knocked B.picked C.took D.shook

16.A.lives B.acts C.thinks D.plays

17.A.task B.lesson C.day D.time

18.A.Here B.There C.So D.Then

19.A.quite B.already C.even D.still

20.A.observe B.discover C.gain D.learn