Unit 4 Inventions第第6 6课时综合提升课时综合提升A B A C B C C A C C A B A B C BCCACAAABBA D C A D B D C B B themselveseasierto setchairssittingmovesfromslowlytheand This is a Doras invention. It is a flying bike. It looks like a normal bike so you can ride on it just as usual. However, it also can fly. Look, there are two propellers and a solar plate which can help you ride the bike more easily. When you push the foot plate with your two plates, the wheels will run and the propellers will work too. In this way, the bike can fly. You can fly on it, too. Besides, it can be charged by the sunshine. It saves resources. Hope you like this invention. I hope the flying bike will become a real one in the future.