题目内容：

句式练习题
1 It is great fun to have a picnic on the hill(感叹句)what( )( )lt( )to have a picnic on the hill!
2 He can't come because he ls lii(改为简单句)He can't come because ( )( )( )
3 Please tell me when to leave for Beijing(改为复合句)Please tell me ( )we ( )leave for Beijing
4 You should give them back to me after you use them(改为简单句)You should give them back to me ( )( )them