保持清醒头脑的英语表达可以有以下几种：
Keep a clear head
Stay alert
Stay sharp
Keep your wits about you
这些表达都指的是保持思路清晰，注意力集中的状态。
例句：
Keep a clear head when you're driving. It's important to stay focused on the road.
Stay alert and pay attention to your surroundings. You never know when danger might strike.
It's important to stay sharp in this fast-paced world. Take breaks and get plenty of rest to keep your mind sharp.
Keep your wits about you when you're travepng in a new place. It's easy to get lost or taken advantage of if you're not careful.
中文翻译：
开车时保持清醒头脑。重要的是集中注意力看路。
注意周围环境，保持警惕。你永远不知道危险什么时候会来临。
在这个快节奏的世界里保持敏锐是很重要的。休息一下，让大脑保持清醒。
在新地方旅行时，保持清醒头脑。如果不小心的话，很容易迷路或者被利用。