`13`. doing `=>` to do

`->` It + takes/took + SO + thời gian + to V

`14`. repaired `=>` had repaired 

`->` After + quá khứ hoàn thành, quá khứ đơn

`15`. for `=>` of

`->` tobe scared of + N/Ving: sợ hãi

`16`. like `=>` likes

`->` "nobody" là đại từ bất định nên động từ thêm "s"

13. It took me two hours doing=>to do my homework last night.

It+take+S+time+toV+N+O

14.14. After the neighbor repaired the skirt, it looked beautifully=>beautiful.

Vì looked+adj.

15.Children are usually scared for=>of seeing the dentist.

16. Nobody like=>likes him because he always looks untidied.

Vì nobody là số ít.