Pressing one's thumb on a table and sometimes stirring it up and down may show that someone has put another person under his thumb.

将拇指按在桌子上，有时上下挑动，表示某人已将另一个人按在拇指下面了，即完全控制某人。

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Ebert's thumb pointing up or down was his trademark.

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Imagine browsing a webpage and running your thumb along the side of your iPhone to scroll up and down.

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Investors who aren't under Uncle Sam's thumb can move their money elsewhere, bidding up prices and driving down yields on other fixed-income assets in the U.S. and offshore.

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