Scientists are trying their best to_______ ways to treat the terrible disease caused by Ebola(埃博拉）．
| A．come up with | B．look forward to |
| C．talk about | D．give up |
We’d better ____ out .It’s going to rain.
A. not to go B. don’t go C. not go
Shanghai is a beautiful city. I _____ there twice .
A. went B. have gone C. have been
He used ___ in the morning , but now he gets used _____ after supper.
A to study, studying
B. to study, to studying
C. to studying , to study
The naughty boy stopped ____ when the teacher went away.
A. play B. to play C. playing
I don’t think it is a good idea, ________ ?
A. isn’t it B. is it C. do we