我不能放松，仍然觉得很清醒。

I could not relax and still felt wide awake.

《柯林斯英汉双解大词典》

开头几天我觉得很恶心，但后来，我的精力大幅增加，头脑也变得前所未有的清醒，就像有种“脑雾”之类的东西被驱散了一般；就像我脑子里的CPU和内存升级了似的。

I felt lousy the first couple days but then my energy surged. I also felt more clear-headed than ever, as if a "fog of brain" had been lifted; it felt like my brain had gotten a CPU and a RAM upgrade.

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想到曾经独自一个人值夜班时他说：“我觉得很难保持清醒，非常非常难。”

"It was very difficult to stay awake, extremely difficult," he said recalling his time on the overnight shift when he was usually the only one on duty.

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