He said,"My sister was here three days ago."改为间接引语怎么改啊?

问题描述:

He said,"My sister was here three days ago."改为间接引语怎么改啊?

He said ,his sister was there three days ago .
很简单嘛,这个一定对。

He said his sister was here three days ago.

改成:He said that his sister had been there three days before.