1.           Kien enjoys to play games in his free time.=> playing 

2.           Shall we seeing a movie this weekend? – Yes, let’s. => see

3.           If he learns hard, he pass the exam. => will pass 

4.           Tam is chating with his pen friend on the internet.=> chatting 

5.           What a intelligent girl! => an

6.           There’s a lot of new books in the school library. => there are 

7.           She isn’t as kind than her elder sister. => as

8.           Mai is the prettiest of the two girls. => prettier 

9.           Which is the best suitable apartment for your family? => most

10.        She looks care of sick people in a hospital. => takes