单项选择题
Shall I get some chalk for you? （）
A.That's right B.No, thanks, let Tom do it C.I can do it without you D.Not at all
单项选择题 Selecting a mobile phone for personal use is no easy task because technology（）so rapidly.
单项选择题 Professor White contributed a lot to our community,（）
单项选择题 Professor Smith promised to look（）my paper, that is, to read it carefully before the thesis defense.
