1.You should brush your teeth after meals.

→Brush your teeth after meals!

2. You should not play soccer in the street.

→Don't play soccer in the street!

3. You should wash and iron your own clothes.

→Wash and iron your own clothes!

4. You should not eat too much candy.

→Don't eat too much candy!

5. You should wash your hands before meals.

→Wash your hands before meals!

6. You should not worry about the examination.

→Don't worry about the examination!

7. You should tidy your room every day.

→Tidy your room everyday!

8. You should not forget to write to your parents.

→Don' t forget to write to your parents!

E,

1,do→did

2,teach→taught

3,send→sent

4,spend→spent

5,begin→began

6,cut→cut

7,put→put

8,give→gave

9,write→wrote

10,be→was/were

11,buy→bought

12,have→had

13,take→took

14,go→went

15,make→made

16,think→thought

17,see→saw

18,eat→ate

19,sing→sang

20,wear→wore

1.Brush your teeth after meals!

2.Don't play soccer in the street!

3.Wash and iron your own clothes!

4.Don't eat too much candy!

5.Wash your hands before meals!

6.Don't worry about the examination!

7.Tidy your room everyday!

8.Don' t forget to write to your parents!

E.

1.do=>did

2.teach=>taught

3.send=>sent

4.spend=>spent

5.begin=>began

6.cut=>cut

7.put=>put

8.give=>gave

9.write=>wrote

10.be=>was/were

11.buy=>bought

12.have=>had

13.take=>took

14.go=>went

15.make=>made

16.think=>thought

17.see=>saw

18.eat=>ate

19.sing=>sang

20.wear=>wore