If you shake the solution, do not use it for one hour.

单选题

If you shake the solution, do not use it for one hour.

答案解析

单选题

for the first time in Britain, they say “How do you do?”and shake hands. Usually they do not shake hands when they just meet or say goodbye. But they shake hands after they haven‘t met for a long time or when they will be away from each other for a long time. Last year a group of German students went to England for a holiday. Their teacher told them that the English people hardly shake hands. So when they met their English friends at the station, they kept their hands behind their backs. The Eng

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单选题

If you see discoloration, replace the part.

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多选题

You should shake hands （）.

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单选题

If you study hard, you ____________ the examination.

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