`18.A`

`19.A`

`20.B`

`21.A`

`22.A`

`------------`

*So sánh hơn:

`\text{- Short adj/adv: }`

`\text{S + tobe/V + adj/adv + -er + than + ... }`

`\text{- Long adj/adv: }`

`\text{S + tobe/V + more + adj/adv + than + ... }`

* So sánh nhất:

`\text{- Short adj/adv: }`

`\text{S + tobe/V + the + adj/adv + -est + ... }`

`\text{- Long adj/adv: }`

`\text{S + tobe/V + the most + adj/adv + ...}`

`@`So sánh ngang bằng `-` adj/adv:
S + tobe/V + as + adj/adv + as + S