.
The reason for their failure, you know, was _______ they didn’t get fully prepared for it.
| A．why | B．whether | C．that | D．what |
Anyone in the lab has to the following dos and don’ts.
| A．observe | B．consult |
| C．recognize | D．direct |
It’s really difficult to ______ what he is trying to express.
| A．leave out | B．pick out |
| C．work out | D．make out |
This camera is of good quality. If it ______ break down within the first year, we would replace it with a new one.
| A．would | B．might | C．could | D．should |
As a green hand, he doesn’t know______ it takes to start a business here.
| A．when | B．how | C．what | D．which |
He is looking for a job, ______ where he can make the most of his talent.
| A．it | B．one |
| C．that | D．the one |