You've got to keep to the speed limit
你必须遵守限速规定。
You should always keep to the speed limit.
什么时候你都不得超过最高速度限制。
Keep to the nearside lane.
不要偏离左边的`车道。
Let's keep to the subject, or you'll get me too confused.
别跑题，否则你会把我搞糊涂的。
He had been unable to keep to his schedule.
他没能遵循自己的计划。