Look ___________ the cucumbers. They are tender and green. [ ]
A. at
B. out
C. for
答案:A
.群体极化
对后张法预应力混凝土结构构件,侧模宜在( )拆除。
A.预应力张拉后B.预应力张拉前C.预应力张拉同时D.预应力张拉后3h内