第3版 Unit. 1. oil 2. killed 3. enemies 4. factories 5. Crops ll. I. recycled 2. less 3. hopcless 4. pollution 5. waste IlI. 1. What will happen 2. Why did 3. be worried about 4. a danger to 5. don't think he works hard 6. don't have to 7. as well IV. 1. will be very happy 2. It's no use asking 3. That means 4. to help 5. to learn ways to 6. I don't think 7. make; a better place V. 1-5 BCAED Unit 2. 1. bottles 2. divided 3. repeating 4. plastic 5. recycling. 1. rapidly 2. cloth 3. to reduce 4. steps 5. Reusing. 1. is harmful to 2. to make a change 3. to turn off 4. to throw away 5. find out IV.. divides; into 2. ask for 3. as useful as 4. It takes energy to. 1. We should use our things as long as possible. 2. Let's go and help Jim so that he can finish the task today.