1. We decided not to go out for meal _________ we were too tired 2. My shoes are dirty. I'd better take them ________before I come in. 3. Who is going to __________ your children when you're at work? 4. Mary's eyes are weak, __________, she has to wear glasses. 5. Our energy will soon come to an end if we don't__________ it. 6. I like bananas, __________my brother doesn't. 7. Can you turn................ the light? It's too dark. 8. There are............ saving methods and inventions to use solar energy. 9. A new air-conditioner will be................... this morning. 10. Scientists are looking for an.............