题目

 My mother's birthday is ______ April 4th. A. on                 B. in                C. for                D. at 答案：A--- Su Xing went to study in Australia at 16 and he lived on himself for many years. --- Oh, dear! He           a lot of difficulties. A．could have gone through                             B．would have gone through C．will have gone through                                D．must have gone through