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？
