Choose the correct sentences with the modals. 1. we should/shouldn’t pollute rivers, lakes and seas. 2. we can/can’t use water for cleaning/washing up. 3. you should/shouldn’t leave water/tap open. 4. people can/can’t save the planet earth. 5. they should/shouldn’t have a bath every day. 6. he should/shouldn’t throw litter into the rivers/lakes/seas. 7. students should/shouldn’t regularly take care and water plant