He refused to tell us whether he ________ (undertake) the job.

How long ________ they ________ (dig) the ditch?

he teacher told them since light ________ (travel) faster than sound,lightning ________ (appear) to go before thunder.

The director recommended that she ________ (study) more English before going abroad.

“Have you moved into the new flat? ” “Not yet. The rooms ________ (paint). ”

He fell asleep immediately last night; he must ________ (be) very tired.

He asked me whether my brother ________ (fly) to Beijing.

A great number of small power stations ________ (set up) in their county since liberation.

Those who’d like to visit the exhibition ________ (sign) your names here.