Katy could think clearly when not under stress.

凯泰在没有精神压力时能够清晰地思考。

If we confuse these three levels, we will not think clearly.

如果我们混淆了这三个等级，我们便不会清晰地思考。

Though the man was badly hurt in the accident, he was still conscious and could think clearly.

尽管这个男人在事故中受了重伤，但他仍旧具有意识且能够清晰地思考。

The only time I can think clearly is when I'm alone.

我能清醒思考的惟一时间就是当我独处时。

He cannot think clearly when he is upset.

他生气的时候无法清楚地思考。