题型:选择题 I ____to go for a walk, but someone called and I couldn't get away.[ ]A. was planning B. has planned C. had planned D. would plan 查看答案
题型:选择题 如图所示,一根绳子绕过定滑轮,一端拴在钩码上,手执另一端,分别用力F1、 F2、F3拉起钩码,实验表明下列说法正确的是:[ ]A.F1较大 B.F2较大C.F3较大 D.三个力一样大 查看答案