1. I suggest (collect/ collected / to collect / collecting) unused clothes.
2. I suggest that we (will put/ putting/ should put/ to put) garbage bins around the school yard.
3. (Why don't we / Let's / How about / What about) turn off the lights before leaving.
What about (to use/ use/used/ using) public buses instead of motorbikes?
She forgot to turn (on/off/ in / to) the gas before going out.
6. What can we do to spend less (in/on/about/ of) lighting?
7. Who looks (for/ at / after / to) your children when you are away from home?
8. Take a shower (in spite of/ replace for / instead of/ instead for) a bath to save energy.
9. She should call a/an (plumber / carpenter / mechanic/ electrician) to repair some cracks in the water
pipes.
10. For most North American households, lighting (amounts for / accounts for / reaches for / access to) 10
percent to 15 percent of the electricity bill.
11. A dripping faucet can (save / take / waste / use) a lot of water.
12. You should (minimize/change
/consume / replace) an ordinary 100-watt light bulb with an energy-saving
one.
13. Lan's eyes are weak, (but/or / however / therefore), she has to wear glasses.