after then和since then的区别

问题描述:

after then和since then的区别
RT

二者都是“从那以后”的意思,都可作连词,一般放在句中
since then 后接完成时,从那以后直到现在
after then后接过去时
如:
I have known her since then.
I kept in touch with her after that.