`1.` That car is not as cheap as this one.

`-` So sánh bằng: Với tính từ: `(-)` S1 + tobe + not + as + adj + as + S2

`2.` The air in the city is often more polluted than that in the countryside.

`-` So sánh hơn: Với tính từ dài: `(+)` S1 + tobe + more + adj + than + S2

`3.` Nobody in Giang's class is better at English than her.

`-` So sánh hơn: Với tính từ ngắn: `(+)` S1 + tobe + adj + -er + than + S2

`-` Trường hợp đặc biệt: good `->` better

`4.` How often do you go to the English Club?

`-` How many times a week + do/does + S + V(bare)?

`=` How often + do/does + S + V(bare)? `->` Hỏi về tần suất

`5.` My brother usually walks to school.

`-` go to swh on foot `=` walk to swh: đi bộ đến nơi nào đó

`-` DHNB: usually `->` Thì HTĐ: `(+)` S + V(s/es)

`-` Vì "My brother" là S số ít `->` V phải thêm "s/es"

`1.` That car is not as cheap as this one.

`->` So sánh ngang bằng `-` adj:
S + tobe + as + adj + as + S

`2.` The air in the city is often more polluted than that in the city.

`->` So sánh hơn `-` adj dài:
S + tobe + more + adj + than + ...

`3.` Nobody in Giang's class is better than her.

`->` So sánh hơn `-` adj ngắn:
S + tobe + adj + -er + than + ...

`4.` How often do you go to the English Club?

`->` How often `+` do/does `+` S `+` V-bare?

`5.` My brother usually walks to school.

`-` go to school on foot `=` walk to school: đi bộ đến trường