nager was worried about the press conference his assistant ______ in his place but, luckily, everything was going on smoothly.

Can you imagine the great difficulty he had ________ his driving test last week?

Have you seen______ pen? I left one here this morning.— Is it___________ black one? I think I saw it somewhere.

He was badly hurt last night. That is _____ he didn’t come to school.

Xinjiang is one of the areassandstorms happen most often,results from a dry climate, vast desert and a strong wind.