I think we should write on both sides of the paper.

- I think we should save plastic bags, clean and reuse them.

- I think we shouldn't throw wastes and garbage into streams, lakes and even oceans.

- I think we should discard/ throw garbage in waste bins.

- I think we should use less private vehicles and don't release pollutants into the air. 

- I think we should try to re-use and recycle things.

Với should:

1. You should clean the beach every day.

2. The Government should severely sanction acts of overexploitation, rampant, improper standards and law.

3.The prime minister should build many good wastewater and waste treatment systems before discharge.

4.The police should intensify environmental inspection, inspection and supervision.

5.You should propagating and raising the awareness of each person about the marine environmental protection.

Với shouldn't:

1. You shouldn't littering.

2.You shouldn't go fishing with electricity, explosives, toxic chemicals.

3.You shouldn't hunt precious animals.

4.Factories should not create too much CO2, causing CO2 concentrations in the sea to rise.

5.You should not use plastic bottle when going to the beach.