`Answer:`

`a.` He sometimes reads books in the afternoon.

`b.` They always play tennis on Saturday.

`c.` My sister always swims in the summer.

`d.` She never goes shopping on Monday.

`e.` He sometimes drives car to his work.

`f.` My sister does her homework in the afternoon.

`g.` I have a shower early in the morning.

`h.` My brother always plays basketball on Sunday.

`i.` My father never goes shopping.

`j.` I always get up early in the morning.

`k.` She sometimes goes to the theater on Sunday.

`I.` My friends always play football on Saturday.

`m.` We always go to the beach on the weekend.

`n.` We never go to the mountains.

`->` Cấu trúc thì Hiện tại đơn:

`(+)` S + Vs/es

`+` Chủ ngữ: I/ they/ we/ you/ N(Số nhiều) `->` động từ giữ nguyên mẫu

`+` Chủ ngữ: It/ she/ he/ N(Số ít) `->` thêm "s/es" vào sau động từ