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　　　　1　　 It might understand more than you think．

A dog named Rico recognizes the names of about 200 objects, say researchers in Germany．　　2　　 Its word-learning skills are as good as those of a parrot or chimpanzee．

In one experiment, the researchers took all 200 items that Rico is supposed to know and divided them into 20 groups of 10 objects．　　3　　 In four tests, Rico got 37 out of 40 commands right．As the dog couldn't see anyone to get clues, the scientists believe Rico must understand the meanings of certain words．

In another experiment, the scientists took one toy that Rico had never seen before and put it in a room with seven toys whose names the dog already knew．　　4　　 The correct object was chosen in seven out of 10 tests, suggesting that the dog had worked out the answer by process of removing．A month later, Rico remembered half of the new names, which is even more impressive．

　　5　　 Even if they do, they can't talk back．Still, it wouldn't hurt to sweet-talk your dog every now and then．You might just get a big, wet kiss in return!

A．The owner then told Rico to fetch the object, using a word the dog had never heard before．

B．Do dogs more understand us than some friends?

C．It's hard to know if all dogs understand at least some of the words we say．

D．Be careful what you say around your dog．

E．The dog also appears to be able to learn new words

F．Then the owner told the dog to go and fetch one of the items and bring it back．

G．Rico is thought to be smarter than the average dog．

阅读下题，根据括号内的汉语提示，用句末括号内的英语单词完成句子。

The air hostess required that ________(我们坐着)until the plane had come to a complete stop．(remain)

阅读下题，根据括号内的汉语提示，用句末括号内的英语单词完成句子。

Did you know ________(到底怎么)the nuclear explosion occurred in Japan?(it)

阅读下题，根据括号内的汉语提示，用句末括号内的英语单词完成句子。

I have no idea whether the machine can be used again but it ________(在维修)in the morning．(repair)

阅读下题，根据括号内的汉语提示，用句末括号内的英语单词完成句子。

Qian Xuesen went to California from 1935 to 1955, ________(在那时期)he concentrated on the research into jet planes．(period)

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He told us that he was very happy ________(他现在的处境)．(be)

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During my last trip my cellphone was left in a hotel accidentally, ________(再也找不到)．(find)

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It's widely accepted that never in history ________(有过)a more successful opening ceremony than that of the Beijing Olympics．(there)

阅读下题，根据括号内的汉语提示，用句末括号内的英语单词完成句子。

________(余下要做的)is an accurate description of the long process of the experiment．(leave)

阅读下题，根据括号内的汉语提示，用句末括号内的英语单词完成句子。

Tom has been playing basketball on the playground, ________(脸上全是汗水)．(cover)