单选题 Mary demanded that he ______ the books he borrowed from her a month ago.

单选题 Every time I met her, she would show her concern ______ me and my family.

单选题 Those ______ are willing to help others are likely to be popular among people.

单选题 The pipe in the kitchen is broken. We should have it ______ as soon as possible.

单选题 We have to accept the fact ______ there is a shortage of qualified teachers in the countryside.

单选题 There are enough night schools in this city. Adults can be educated no matter ______ old they are.

单选题 By the time he retires, Carl ______ president for 15 years at the university.

单选题 —Did you find the film boring? —Not at all. It was ______.