bài 1: put one suitable preposition to complete the senteces:
1.My mother takes of ........... the family
2.I smiled ............. the child and said 'Hello'
3.She is always worried ............ her children
4. Milk is good ............your health
5.Most children are scared ............... seeing the dentist
6.The dentist looked ............... my teeth
7.Mr.Thanh has an appointment .................. 4 o'clock this afternoon
8.Yesterday the dentist filled a cavity ................. my tooth
9.What 's wrong ............... Sue?
10.Mrs .Quyen is a very good doctor .She look ............sick people very carefully