1 ) Circle correct answer.
a.You should / shouldn’t use public transportation .
b.We should /shouldn’t destroy rainforests.
c.You should/shouldn’t walk on the grass.
d.People should/shouldn’t be more careful about trees.
e.You should /shouldn’t waste energy.
2 ) Must or Mustn’t ? Write True or False.
a. You must eat healthy food. _______
b. We must cut down the trees _______
c. We mustn’t use solar energy. _______
d. We must recycle glass, metal and plastic. _______
e. We mustn’t use energy-saving bulbs. _______
3 ) Fill in the blanks with “has to” ,”have to” ,”doesn’t have to” or ” don’t have to” .
a. People ___________________ stop wasting energy.
b. I ___________ use plastic bags. I can use paper bags.
c. My brother is a student. He _____________ wear uniform at school.
d. We _____________ keep environment clean.
e. She is ill. Doctor says she _____________ rest.