液压油是传递压力的媒介，同时又是液压传动系统中部件的（）。

Mr. Green：Hello! This is English－help Centre.   1 
Li Lei：Yes. I have some problems with English.
Mr. Green：  2 
Li Lei：First, I can’t speak English well.
Mr. Green：  3  Why not join a language club to practice English?
Li Lei：OK, I’ll try it. Also I can’t understand the teacher when she talks to the class.
Mr. Green：Listening to more tapes will help a lot. Remembering the words of English songs also helps a lot.
Li Lei： 4  I’ll do that as much as possible.
Mr. Green：You’re welcome.   5 

A. Don’t worry. B. I hope your English will improve soon. C. Can I help you? D. Thank you very much. E. What are your problems?

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