单项选择题
The diligent student refused the help of others and insisted on working out the difficult maths problem ______.
单项选择题 The old man took the boy ______ the hand and walked away.
单项选择题 ______ all the subjects, he is best ______ English.
单项选择题 Can't you keep your dog ______ coming into my yard It is always disturbing us.
