换热器按原理分为三类：（）、（）、（）。
参考答案：间壁式、蓄热式、混合式
You are not a child ___.You should do every thing by yourself
A．no longer
B．any long
C．no more
D．any longer
Everybody likes to get along with someone who is generous _____ his money and dislikes ____with
someone who is mean with it. [ ]
A. with; to get along
B. for; getting
C. with; getting
D. to; to get along
