I was tired out, so I stopped the car a short rest.
A:have
B:having
C:to have
D:had
如图是唾液消化淀粉的实验过程装置图,请分析回答下列问题:
正处于生长发育时期的青少年,应多吃下列哪一组食物( )
某商店购买60件A商品和30件B商品共用了1080元,购买50件A商品和20件B商品共用了880元.