Having a walk after supper is certainly good for the old people, but it remains ______ whether they will enjoy it.
| A．to see | B．to be seen | C．seeing | D．seen |
What great trouble the boy _____his father to give up smoking!
| A．had to persuade | B．had persuaded |
| C．had persuading | D．had persuade |
“I called you yesterday. A woman answered, but I didn’t recognize her voice.” “Oh, it _____ my aunt Jean.”
| A．must be | B．must have been | C．might be | D．can have been |
Anyone _______ bags, boxes, or whatever, was stopped by the police.
| A．seen carry | B．seen carrying | C．saw to carry | D．saw carrying |
---Why did the policeman question Tom?
---He was ________of taking part in the killing.
| A． doubted | B．suspected | C．charged | D．accused |
______ the teacher has given permission, ______allowed to use the equipment in the lab.
| A．Only if, are the students | B．If only, the students are |
| C．If only, are the students | D．Only if the students are |