You've got to keep to the speed limit.

你必须遵守限速的规定。

You should always keep to the speed limit.

什么时候你都不得超过最高速度限制。

Let's keep to the subject, or you'll get me too confused.

咱们不要离题，否则你会把我弄得很糊涂。

Keep to the right, please.

请靠右行驶。

This room and the next are where you'll live—and you must keep to them.

这个房间和隔壁房间是你住的地方，你必须呆在里面。