语法改错题

after the teacher arrived, the lesson began.

The lesson began after the teacher arrived./
After the teacher arrived, the lesson began.

after the teacher`s arriving , the lesson began.

看错题了,汗一个.

after the arrival of teacher, the lesson began.

arrived的意思是到达，teacher的意思是老师。
病句的意思是：在到达老师以后，课就开始了！
这肯定不对！应该是“在老师到达以后”所以：
After the teacher arrived, the lesson began.