The negative form is should + not, we usually get the contraction shouldn't.
EXERCISES
1.- Use these verbs to give some advices to your friends:
- use.................................................................
- speak.............................................................
- recycle...........................................................
- save...............................................................
- play...............................................................
- study.............................................................
- My friends are very tired. They.......................go to bed early.
- You ...................ride your bike carefully, this road is too dangerous.
- I ....................finish my homework, the test will be next week.
- Peter ....................help his parents, they are cleaning the house.
- It's raining, she.....................take her coat.
- It's snowing, we........................play the match.
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