随着地下建筑大规模的发展,工程建筑的()等方面因素越来越受到重视。
A、经济
B、安全
C、环保
D、质量
E、耐久
参考答案:A, B, C, E
Not until I dropped off from school ____ how much time I had wasted.
A.didn't I realize
B.did I realize
C.I didn't realize
D.I realized
由两种或两种以上的不同圈闭混合而形成的圈闭叫做非构造圈闭。