themselves的造句

问题描述:

themselves的造句

They finish their homework by themselves.
他们自己完成作业.
They go to school by themselves.
他们自己上学.
They themselves are to blame.
是他们自己不好.
I hope that they can make it by themselves.
我希望他们能靠自己成功.
by用于themselves前面,可加可不加.