1. No one in my class is taller than Peter 

-> Peter is the tallest in my class.

=> Giải thích : so sánh nhất với tính từ ngắn

2. The black dress is more expensive than the white one

-> The white dress is cheaper than the black dress  

=> Giải thích : so sánh hơn với tính từ ngắn

3. No one in my group is more intelligent than Mary

-> Mary is the most intelligent in my group

=> Giải thích : so sánh nhất với tính từ dài

No river in the world is longer than the Nile

-> The Nile is the longest river in the world.

=> Giải thích : so sánh nhất với tính từ ngắn 

1. Peter is the tallest (student) in my class.

- No one + in (place) + tobe + adj + "-er" + than + S

= S + tobe + the + adj + "-est" + N + in (place)

2. The white dress is cheaper than the black one.

@ Cấu trúc so sánh hơn với adj-ngắn:

- S1 + tobe + adj + "-er" + than + S2

3. Mary is the most intelligent in my group.

- No one + in (place) + tobe + adj + "-er" + than + S

= S + tobe + the + adj + "-est" + N + in (place)

4. The Nile is the longest river in the world.

- No + N + in (place) + tobe + adj + "-er" + than + S

= S + tobe + the + adj + "-est" + N + in (place)