1. You must never take your helmet off while you are riding a motorcycle. (all) -> Helmet must be worn.......................... 2. They wanted to apologize for their behaviors: that's why they paid for dinner. (order) -> They paid for dinner............................. 3. Do you think you could give me a hand to move the sofa? (mind) -> Would you.............................................. 4. He doesn't have enough money to buy the computer. (too) -> The computer........................................ 5. I could never have passed that exam without your help. (you) -> I could never..........................................

`1.` Helmet must be worn at all times while riding a motorcycle.

`-` BD ĐTKT : S + ĐTKT + be + Vpp + (by O) 

`2.` They paid for dinner in order to apologize for their behaviors.

`-`  paid for sth : trả tiền cho cái gì đó

`-`  S + V + in order + to V : để làm gì  

`3.` Would you mind giving me a hand to move the sofa?

`-` Would you mind doing sb/sth : Bạn có thể làm gì đó không?

`4.` The computer is too expensive for him to buy.

`-` enough money to do sth : đủ tiền để làm gì đó

`-` too adj for sb to V : quá đến nỗi mà

`5.` I could never have passed that exam if it hadn't been for you.

`-` CĐKL 3 : If + S + had + V (quá khứ phân từ), S + would/could/might + have + Vpp

`->` Diễn tả một điều kiện không có thật trong quá khứ và kết quả giả định nếu điều kiện đó xảy ra.