She committed a silly mistake.

她犯了一个愚蠢的错误。

youdao

You make a silly mistake and lose.

你犯了一个愚蠢的错误并且输掉了。

youdao

Why did I make such a silly mistake again?

我怎么又犯这样愚蠢的错误。

youdao

How can you make such a silly mistake?

你怎么会犯那么傻的错误？

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It's a silly penalty, a silly mistake now and again that has cost us.

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You can only imagine the frustration of having months of hard work go to waste because of a silly mistake.

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That was a silly mistake.

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