中层理论
参考答案：
指介于日常研究中低层次的而又必须的操作假设与无所不包的系统化的统一理论之间的那类理论。
Playing sports is a good way to have fun.Kangkang often _____小题1:____(go) to the school gym to do sports.Last Saturday,Kangkang _______小题2:____ (go) to the gym with some of his classmates. They ____小题3:___ (have) great fun swimming and playing basketball.
小题1:
小题2:
小题3:
It is Friday today. Look！Kangkang and Michael ______小题4:____ (play) table tennis while Lily is learning to skate.What will they do tomorrow? They ____小题5:______ (go) to the zoo. They will be very happy！
小题4:
小题5:
进口货物适用哪种税率，决定于（）。
