The boy went to sleep after his mother come back(改为同义句）He was_____yesterday afternoon,_____he didn't go to the concert
问题描述：
The boy went to sleep after his mother come back(改为同义句）
He was_____yesterday afternoon,_____he didn't go to the concert
答
The boy didn't go to sleep until his mother came back.
补充：
busy；so
答
楼上的第一句改为
The boy didn't go to sleep until his mother came back.
把befor改为until更好一点
答
The boy didn't go to sleep until his mother came back.
so busy ;that
答
待解决：
The boy didn't go to sleep before his mother came back.
问题补充：
He was busy yesterday afternoon,so he didn't go to the concert.