III
1,B:an⇒a
2,B:fluent⇒more fluently
3,A:with⇒up
4,A:has⇒have
5,A:don't⇒∅
IV
1,dog can swim better than cat
2,minh really enjoy hanging out with friends
3,it's very interesting to play beach games
4,he spend all his free time looking after his garden
5,do you mind changing this t-shirt for me
V
1,A
2,A
3,B
4,(sai đề enjoy + V_ing/to verb)
5,T
6,F
7,T
8,F