---- Do you mind if I smoke?
----________.
| A．Why not? | B．Yes, help yourself. |
| C．Go ahead. | D．Yes, but you’d better not. |
In much of the animal world, night is the time ______ for sleep – pure and simple.
| A．set aside | B．set down | C．set off | D．set up |
--Thank you for the suggestions you kindly offered us.
--______. It is really an honor to help you.
| A．Don’t mention it | B．Go ahead |
| C．Don’t worry about it | D．Go away |
--You’ve got your flat furnished, haven’t you?
--Yes, I ______ some used furniture and it was a real bargain.
| A．will buy | B．have bought | C．had bought | D．bought |
The world is more forgiving than commonly ______, so we should be optimistic about life.
| A．declared | B．promoted | C．supposed | D．required |
I still remember the accident and the troubles ______ has caused to me.
| A．which | B．what | C．it | D．that |