1）I still remember the day I first came to Beijing．
I spent with you 
in Beijing．
2）①They have reached th
e point they have to separate with each other
②There is one point we must insist on．
3）We are living in an age many things are done on computer．
4）①I can think of many cases students obviously know a lot of English words and expressions but couldn't write a good essay．
②I can think of many cases you know nothing about．
