Ex 2. Choose the best answer to fill in the blank. 1. Robots can ________ our houses when we are away. A. look B. guard C. look at D. see 2. “Reduce, reuse, recycle” is said to encourage people to waste less, by using less and using things again, in order to ________ the environment. A. harm B. protect C. pollute D. damage 3. It is a good idea to ________ our clothes with our friends or cousins. A. turn B. swap C. send D. change 4. Robots will be very useful for our lives but they use ________ energy. A. too much B. some C. alittle D. very 5. I might have a smart phone ________ the Internet. A. surf B. surfing C. to surf D. to surfing 6. I don't agree ________ you that robots will be able to write a letter to an English friend. A. to B. with C. about D. of 7. “Don't throw rubbish into the river because you will make it ________”. A. dirty B. fresher C. cleaner D. greener 8. Robots will do most of the housework, ________ we will have more time for our family. A. but B. although C. if D. so 9. “What can we do ________ air pollution?” A. reducing B. to reduce C. reduce D. to reducing 10. If people can ________ wastes, they will save a lot of money. A. rebuild B. reduce C. reuse D. use