Jack, go and get some chalk, ___?
A.will you
B.shall we
C.do you
D.shan’t we
答案:A
缺乏实测资料时,怎样推求设计年径流量?
讲解与示范相结合效果最差的是()
A.又听又看
B.只看不听
C.只听不看