如果一位公开演讲的人，在给你们作报告时，他老是在摆弄一支铅笔或者是摆弄他的眼镜，那么，他这是很清楚告诉你，他心情很紧张。
If a public speaker (like a professor, for example) is all the time fiddling with a pencil, or with his glasses, while he is talking to you, he is telling you quite clearly that he is nervous.
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