Scientists photographed for the first time ever _____ wild gorillas used a stick to test the depth of a pool before getting into it, according to a recent study.
| A．which | B．what | C．that | D．when |
When ____ , the library will be open to the public next year.
| A．completing | B．being completed | C．to be completed | D．completed |
Will you drop in at my house this afternoon if ____?
| A．you are convenient | B．you will be convenient |
| C．it is convenient | D．it will be convenient |
She fully____ the humor of her role in the play and made it a great success.
| A．exported | B．explored | C．exploited | D．exploded |
Don’t worry and I’ll get your car fixed ___ .
| A．at no time | B．in no time | C．at a time | D．at all times |
---- Look! Everything here is under construction.
---- Oh, has the building once ___ for exhibition been pulled down, too?
| A．having been built | B．being built | C．to be built | D．built |