1- They didn't let me to go.

They didn't let me go.(chỉ có cấu trức to go to sth)

2- She failed her examination like her friend did.( 

She failed her examination as her friend did.( like + ving hoặc  vinfi )

3- I buy a new house if I have enough money.

 I will buy a new house if I have enough money. ( cấu trúc if1 : if +s1+htd,s2+will + Vinfi)

4- He has learnt Chinese enough to study in China.

He has learnt enough Chinese to study in China.( cấu trúc : S + V/tobe + enough + noun + (for somebody) + to V

5- Nobody have used this house for a long time.

Nobody has used this house for a long time.( everyone,everybody No one, đi với trợ động từ has trong qkht)

6- His garden isn't as large than mine.

His garden isn't as large as mine.(so sánh = )

7- We haven't talked to your sister since a long time.

 We haven't talked to your sister for a long time.  ( vì có haven't nên là qkht phải dùng for a long time ; since along time : qkđ

8- There are much than eighty stores in the mall.

There are more than eighty stores in the mall ( so sánh hơn không dùng much )