It means to scratch your head in order to help you remember something you've forgotten.

这意味着你抓耳挠腮以使自己想起你遗忘的东西。

youdao

If he scratches his head, you scratch your head.

如果他挠头，你也挠头。

youdao

You scratch your head and the only thing I can think of is that it's the pressure.

你想破头也不会明白，我觉得唯一的答案就是压力。

youdao

"You sort of scratch your head as a consultant when you hear the manufacturer suggest they curb production, " says Mark Rikess, who runs a dealership training and consultancy in Burbank, Calif.

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It makes you scratch your head about the actual role of the public schools since there is so much spent on staff other than teachers relative to other nations.

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Before you scratch your head, consider: The San Francisco 49ers posted a 104-47 record--the league's best, including four championships--during the 1980s, yet the team that lost the most money during that decade was, ahem, the 49ers.

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