用活塞压缩气缸中的空气，对空气做功1200J，同时气缸向外散热300J，气缸内空气热力学能如何改变？改变了多少？
The auto manufacturers found themselve____ foreign firms____market share.
A. compete with; on
B. competing with; for
C. competing with; about
D. competed with; for
To be frank, I like____ , but now I don't like ____today because of the bad weather.
A. fishing; fishing
B. to fish; to fish
C. to fish; fishing
D. fishing; to fish
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