`1` She forgot to go to the dentist's .

`-` forget + to V : quên làm gì .

`2` If Mary had enough money , she could buy a new car .

`-` ĐK2 : If + S + V(quá khứ)/were + O , S + could/would + V-inf + O .

`3` A new school is going to be built next year .

`-` Bị động tương lai gần : S(bị động) + is/am/are + going to be + V3/Vpp + O .

`4` I have not seen her for three years .

`-` Hiện tại hoàn thành : S + have/has + V3/Vpp + O .

1. She forgot to go to the dentist’s.

forgot + to V: quên làm gì

2. If Mary had enough money, she could buy a new car.

If loại 2: If +QKĐ, S + would/ could + V1 

3. A new school is going to be built next year.

S + am/is/are + going to be + V3/ed (thì TLG - bị động)

4. I have not seen her for three years.

S + has/have + not + V3/ed + for/since + time 

--> S + last + V2/ed 

--> The last time + S+ V2/ed + was + time 

--> It is / has been + time + since + S+ (last) + V2/ed 

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