Miss Finkelstein will put a dressing on your thumb.

芬克尔斯坦小姐将在你的大拇指上包一层敷料。

《柯林斯英汉双解大词典》

They are so small that they can fit under your thumb.

它们非常小，完全可以放在你的拇指下。

youdao

So are you fast at writing the messages with your thumb?

那么，你用拇指输入信息的速度快吗？

youdao

Then pinch the new shoots between your thumb and forefinger.

VOA: special.2009.10.06

Middle finger exactly and your thumb.

中指和姆指。

哈佛公开课 - 幸福课课程节选

So-- if you don't feel comfortable doing it, don't do it-- what I'd like to do now is as following: Take your thumb and your middle finger and create as much as possible a 90 degree angle.

感觉不舒服的，就不要做，希望按下面的指示做：,让你的姆指和中指,尽可能形成一个直角。

哈佛公开课 - 幸福课课程节选

Then simply place your thumb on the center control to navigate easily through the game.

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Hold one of your hands up, palm out, and cross your thumb over it.

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Imagine a repertoire of simple hand gestures: say, touching your thumb to each of your four fingers.

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