.
The problem, according to the experts, is ________ we should do with the salty land.
| A．what | B．whether | C．how | D．that |
________ you have seen things like these before doesn't matter.
| A．If | B．Whether | C．What | D．When |
You will easily know ________ video recorders are the same.
| A．what those | B．that of those | C．that all of | D．which of those |
Can you point out ________ two radios are the best
| A．which | B．what | C．that | D．whether |
We should think carefully about ________ Mr. Needham said at the meeting.
| A．that | B．what | C．which | D．X |
Jack was soon told ________ he did was not necessary.
| A．why | B．that | C．how | D．why what |