人教版选修7_Unit+1+Living+well+Grammar(共28张PPT)
人教版选修7_Unit+1+Living+well+Grammar(共28张PPT)第2页

结构 : to do (否定) not to do

二. 时态与语态

不定式

to do

to be done

to be doing

to have done

to have been done

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