早上8：00上课，一节课40分钟，那么第一节课下课的时间是[ ]
A.8：40
B.4：40
C.8：20
答案：A
Considering all that she had _______, she was really an amazingly cheerful woman.
A．gone for
B．gone through
C．gone in for
D．gone about
立井用防坠器有哪几部分组成？
