-What's your favorite ? -Surmmer. Because I can swim in the river in summer.
Please pass me the cartoon book ________ has a Mickey Mouse on the cover.
I hate people _______ talk much but do little.
---Where is the scientist ________ gave us the talk yesterday? ---He has gone back to Qinghua University.
The letter _______ I received from him yesterday is very important.
---Does the teacher know everybody _______ planted the trees?· ---Yes, he does.