V.

$\text{1.}$ younger

$\text{2.}$ older

$\text{3.}$ slimmer

$\text{→}$ trước phụ âm là 1 nguyên âm thì nhân đôi phụ âm thêm -er

$\text{4.}$ shorter

$\text{5.}$ fatter

$\text{6.}$ shorter

$\text{7.}$ uglier

$\text{→}$ nếu kết thúc là đuôi -y <trừ adv> thì bỏ y thêm -ier

$\text{8.}$ slower

$\text{9.}$ tidier

$\text{10.}$ more beautiful

$\text{11.}$ longer

$\text{12.}$ better

$\text{→}$ good/ well - better - the best

$\text{13.}$ faster

$\text{14.}$ worse

$\text{→}$ bad/ badly - worse - the worst

$\text{15.}$ more intelligent

$\text{16.}$ more interesting

$\text{* So sánh hơn:}$

$\text{→}$ Adj/ adv ngắn: S1 + V/ be + adj/ adv -er + than + S2.

$\text{→}$ Adj/ adv dài: S1 + V/ be + more + adj/ adv + than + S2.