6.My sister cannot cook as well as my mother

7.I've never seen a more intelligent girl than her

8.There are more people in big cities than in the country

9.He was too tired to go to work yesterday

10.John is the best play in our team

11.How can you tell to get to the station?

12.The bridge are going to be repaired next month

13.Why don't we go for a walk?

14.It is such a heavy box that i can't lift it

15.The keys was left on the desk

Giải thích :

6.So sánh ngang bằng : be/V + as adj/adv as +...

7.S + have never + V + O : chưa bao h lm điều gì đó

8.So sánh hơn : more...than

9.be + too + adj (for sb) + to V

10.So sánh nhất : the most + adj/the adj + est

11.How can + S tell + sb the way to + sth

12.BĐ : be(am/is/are) + going to V→be(am/is/are) + going to be + Vp2

13.Should + Vo→Why don't we + Vo?

14.It is such + (a/an/the) + adj + N that + MĐ

15.BĐ : be(was/were) + Vp2