地球五带中,有太阳直射现象的是[ ]
A.热带
B.南温带
C.北寒带
D.北温带
答案:A
I wish I ___ able to tell him all about it last night. [ ]
A. should be
B. were
C. had been
D. was
单轨吊制动装置的组成及其功能?