【2012黑龙江齐齐哈尔】The math problem is so hard. I really don’t know_____. A. how to do it B. how to do C. what to do it
This man has _________ friends because he is not friendly.
Who taught them to ride bicycles? __________ They taught __________.
Are you reading a newspaper? Did you find __________ in it?
—We can have a day out tomorrow. Why don't we go fishing ? —________
Jack is _________boy of the twins.