接入网的基本拓扑结构为()。
A.星形结构
B.总线形结构
C.环形结构
D.A.B.C都是
参考答案:D
— Where is it?
— _________________[ ]
A. It's on the chair.
B. I'm sad.
C. I feel tired.
There's only ten minutes to go. We can't wait any more- ______, we should start at once.
[ ]
A. what's more
B. in a word
C. in other words
D. in the end