當後車輪沒有被壓貼向車底時，上链后后轮不会转动.把車放在地上即車輪壓貼

當後車輪沒有被壓貼向車底時，上链后后轮不会转动.把車放在地上即車輪壓貼向車底，後車輪會轉動車會向前行

結果 (英文) 1:

When the rear wheels are not pressed against the bottom of the vehicle, the rear wheel on the chain does not rotate. Put car wheels on the ground that is pressed against the bottom of the vehicle, the rear wheels will turn the car will move forward

結果 (英文) 2:

When the wheel has not been pressed to the bottom, on the chain after the rear wheel does not rotate. Put the car on the ground that the wheel is attached to the bottom, rear wheel will rotate the car will move forward

結果 (英文) 3:

When the back end of car to car round without a pressure wrap around labeling when after chain on the back wheels will not turn. put the car on the ground end of car to car round pressure wrap around labeling, to turn mobile car car round after meeting meeting forward