Pierre Curie ______ his own research work and joined Madam Curie in the search for radium.    

The meeting was _____ when the chairman fell ill.

We should never _____ ourselves with a little book knowledge only.

Tell the boy to ______ all lights as he leaves the room.

 —My spoken English is poor,  what shall I do? —＿＿＿an English language club to practice,  and you’ll be good at it.