课程代码：00794
Ⅰ. 用适当语法形式或词汇填空。从A、B、C和D四个选项中选出一个最佳答案，并填在答题纸相应的位置上。（本大题共30小题，每小题1分，共30分）
1．It is ______________ problem that few people can solve it.
A．such difficult a                                    B．such difficult
C．so difficult a                                        D．so difficult
2．You’d better be more careful with your work,______________?
A．would you                                          B．wouldn’t you
C．had you                                              D．hadn’t you
3．Till then, John ______________ from his sister for about half a year .
A．hadn’t heard                                        B．didn’t hear
C．hasn’t heard                                        D．won’t have heard
4．I hear that all those houses in the street _______________ by the time you come back.
A．will pull down                                     B．will have been pulled down
C．will be pulled down                              D．will have pulled down
5．It is essential that your application form _______________ back before the deadline.
A．must be sent                                       B．would be sent
C．be sent                                               D．will be sent