12. We won’t celebrate the festival. It costs too much money. If ............................................................................................................ 13. This is the first time I have ever met such a pretty girl. She ......................................................................................................... 14. He doesn’t play tennis as well as he used to. He used to ................................................................................................... 15. Last week , she spent 2 days tidying her room. It took ...................................................................................................... 16. It took him twelve hours to fly from Hanoi to London. He spent ................................................................................................... Giúp em với mọi người ơi, làm nhanh em vote 5 sao luôn ạ em cảm ơn mọi người nhiều huhu

`12.` If we celebrate the festival, it will cost too much money.

`->` ĐK1 : If + S + V(s/es) + O, S + will + V.

`13.` She is the prettiest girl I have ever met.

`->` S + tobe + the + adj-est/most adj + S + have/has + ever + P2.

`14.` He used to play tennis better than he does.

`->` SS hơn : S +  V + adv-er/more adv + than + S.

`15.` It took her 2 days to tidy her room last week.

`->` It + takes/took + sb + time + to V : Mất bao lâu làm gì

`16.` He spent twelve hours flying from Hanoi to London.

`->` Spend + time + Ving : Dành bao lâu làm gì

12. If it costs too much money, we won't celebrate the festival.

Giải thích: Câu điều kiện loại 1:

                       If + S + V hiện tại đơn, S + will/can/may/must + Vng.mẫu

13. I haven't met such a pretty girl before.

Giải thích: Cấu trúc Lần đầu tiên (The first time):

                         S + have/has + not + Ved/3 + before

14. He used to play tennis better than he does now

Giải thích:  S + used to + Vng.mẫu

15. It took her 2 days to tidy her room last week.

Giải thích: Cấu trúc Dành bao nhiêu thời gian để làm gì:

                  It + take (took) + O + Khoảng thời gian + to V

16. He spent twelve hours flying from Hanoi to London.

Giải thích: Cấu trúc Dành bao nhiêu thời gian để làm gì:

                     S + spend (spent) + Khoảng thời gian + Ving