_____ he has done it is surprising.
_____ he has done is surprising.
| A．What | B．That | C．Whether | D．If |
Here is such a difficult text _____ none of us can understand.
Here is such a difficult text _____ none of us can understand it.
| A．as | B．which | C．that | D．where |
—Which of these two dictionaries will you buy？
—I'll buy _____ ,for the different uses.
| A．both | B．neither | C．either | D．all |
I didn't know _____ you were getting on well with your work.
| A．because | B．how | C．that | D．which |
Mr Black _____ his wife to teach their child a lesson. So he did.
| A．promised | B．persuaded | C．wanted | D．told |