SS tt/ tt ngắn : S + V + Adj/Adv + er + than
tt/ tt dài : S + V + more + Adj/Adv + than
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$\text{1. more convient }$
$\text{2. younger }$
$\text{3. taller }$
$\text{4. smatter }$
$\text{5. more exciting }$
$\text{6. less }$
-> HT đặc biệt
$\text{7. worse }$
-> HT đặc biệt
$\text{8. more clever }$
$\text{9.more expensive }$