I think students can have mobile phones to help with their studies．
_______．They often use them to play games．（ ）
A．I think soB．I don't agree
C．No problemD．That's a good idea
I wish you a happy National Day!
_____．（ ）
| A． |
The same as you |
| B． |
Thank you |
| C． |
The same to you |
It's already tens of years____the world's population reached five billion．（ ）
| A． |
before |
B． |
after |
C． |
since |
We must remember____．（ ）
| A． |
what our teacher said |
| B． |
what did our teacher say |
| C． |
what has our teacher said |
We don't know if our friend ____．If he____，we'll let you know．（ ）
| A． |
comes；comes |
| B． |
comes；will come |
| C． |
will come；comes |
It's getting dark．You'd better ____out by yourself．It's dangerous．（ ）
| A． |
not go |
B． |
not to go |
C． |
to go |