`1`. I enjoy playing sports because it is good for my health.

`->` S + enjoy + V-ing: thích làm gì

`->` HTĐ: S + am/is/are

`2`. Last month, we planted trees in the park.

`->` QKĐ: S + V-ed/c2

`3`. On Monday and Thursday afternoons, he joins different outdoor activities.

`->` on + ngày trong tuần

`->` HTĐ: S + V(-s/es)

`4`. This camera is not as expensive as I thought at first.

`->` So sánh bằng phủ định: S1 + be + not + as + adj + as + S2

`5`. Lan likes talking to her friends in her free time.

`->` S + like + V-ing: thích làm gì

`->` in free time: trong thời gian rảnh rỗi

`6`. My sister always plays volleyball at the weekends.

`->` at the weekends: vào cuối tuần

`7`. Where did you and your friends go last week?

`->` QKĐ: Did + S + V-inf?

`8`. There is a glass of orange juice in the fridge.

`->` There is + a/an + N-số ít

`->` a glass of + N: một cốc