We were busy ________ (get) things ready for the trial production when he phoned us.

A beam of light will not bend round corners unless ________ (make) to do so with the help of a reflecting device

Night ________ (fall), we hurried home.

I wonder if he could get it ________ (do) before tomorrow.

Matter is the name ________ (give) to everything which has weight and occupies space.

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.