We __________ recycle paper, glass, plastic bags, dead batteries, etc.
should
We __________ collect garbage.
should
We __________ pollute the seas.
should not / shouldn't
We __________ clean up after picnic.
should
We __________ plant more trees.
should
We __________ unplug electrical devices when not in use.
should
We __________ waste water with long showers.
should not / shouldn't
We __________ cut down trees.
should not / shouldn't
We __________ throw the rubbish around.
should not / shouldn't
We __________ turn off the lights when not in use.
should
We __________ pollute the air.
should not / shouldn't
We __________ use public transportation and reduce pollution.
should