9. Christmas is celebrated on the 25th December. 
Bị động với hiện tại đơn: is/am/are+Vpp2
10. Why. don't we go to the dancing hall tonight?
Cấu trúc: How about+ V-ing = Why don't we + V
11.  He is spent Christmas this year being  with his family 
13. It take her 2 days ti rehearse the play
Cấu trúc: S + Spend + time/money + Ving/N…
→ It takes + somebody + time/money + to Vinf…
14.  It's time you learned to look after yourself.
+ It's (high) time + (for O) + to-inf: đến lúc để ai làm gì
= It's (high) time + S (từ O) + V2/ed: đến lúc ai làm gì
15. The chair is so small that he cann't sit on
Cấu trúc So that Với Tính từ/Trạng từ: 
So + Tính từ / Trạng từ + That + Kết quả
=>  The chair isn't big enough for him to sit on it
Cấu trúc: S + be + adj + enough + (for somebody) + to V