Ex: khoanh vào đáp án đúng 1. The monowheel looks futuristic, but it can fall ______ very easily a. up b. down c. over d. out 2. Natural gas is limited and it is harmful ______ the environment a. for b. in c. with d. to 3. If you turn off the light when you leave the room, you'll use _____ energy. a. fewer b. less c. more d. most 4. I didn't have my mobile, so Peter lent me _____. a. mine b. his c. their d. hers 5. I'd prefer to have a _____ that can take me to another place in seconds. a.teleporter b. monowheel c. hover scooter d. flying car