Now one of the most serious problems many people are worried about _____ on the lack of adequate housing space.

Having been trained for one and a half years, she managed to get a professional qualification           a first – degree nurse.

It is impossible to live in society and independent of society; and therefore it is difficult to      
society of      inequality as well as corruption.

The workers could hardly        the boss’s bad temper but under his supervision they had to             themselves to working harder.

--- You promised to call me last night.
--- I called, but I just couldn’t _______.

________ to use in April, 2010, the road has solved the long-standing problem of traffic jams
of this area.

According to the air traffic rules, you should ________ off your mobile phone before
boarding.

Despite the language ________, they soon became good friends.

You’ve ________ the most important word in this sentence. 

They suggested that the professor          just now should be made chairman of the meeting.