Don't grab the brake levers suddenly while riding fast. You could fall.

当你骑很快的时候，不要突然抓住刹车握把。你会摔倒。

There were no controls to bother with except a brake lever and a kind of joystick with a twist-grip accelerator which the girl held fully open with the speedometer steady at thirty.

除了一个制动杆和一种带有扭握式加速器的操纵杆外， 没有其他控制装置可打扰， 女孩将其完全打开， 速度表稳定在三十。