`7`. It's dangerous to ride a bicycle so fast.

`->` Ving + be + adj = It + be + adj + to V 

`8`. Because he was lazy, he failed the exam.

`->` Because + S + V = because of + N/Ving: bởi vì 

`9`. He is very tired but he has to finish his homework.

`->` but : nhưng `->` nói hai vế tương phản

`10`. Although the room is very small, it is quite comfortable.

`->` Although + S + V: mặc dù 

`11`. I like watching TV and going to the cinema.

`->` and : và `->` nối hai vế bổ sung nhau

`12`. He forgot his umbrella; therefore, he got wet.

`->` therefore + S + V: vì vậy `->` chỉ kết quả