根据所给提示，完成句型转换。每空一词，（含缩略词）。

1．She used to work very late last night．（改为否定句）

She                   to work very late last night．

2．I'll fly．to Mexico if I have time．（改为虚拟语气的句子）

I         fly to Mexico if I       time．

3．Parents should allow children to choose their own clothes．（变被动语态）

Children should                    to choose their own clothes．

4．I think this dictionary must be Tom's．（同义句）

I think this dictionary must                  Tom．

5．He likes singers．They can write their own music．（合并为含有定语从句的复合句）

He likes                   can write their own music．