单项选择题To our surprise, the stranger ______ to be an old friend of my mother's.
单项选择题The police still haven' t found her, but they' re doing all they()
A. may B. can C. must D. will
单项选择题It was the doctor's carelessness that ______ the serious accident.
单项选择题How much ______ she looked without her glasses!
单项选择题The air of countryside is cleaner than ______ of city, but I don't like to live ______ far.