The revenue from tourism is the biggest single item in the country's invisible earnings.

旅游收入是该国非贸易性收益中最大的单项收入。

《柯林斯英汉双解大词典》

The computer was my largest single item of expenditure.

电脑是我花钱最多的一件东西。

《牛津词典》

A single item can take at least several weeks to complete.

一项任务至少需要几个星期才能完成。

youdao

Well, I mean the definite article "the", you use when there's only a single specific item that you're talking about.

当你谈论一个特定的项目时，就用定冠词“the” 。

经常犯的失误 - SpeakingMax英语口语达人

But with Bitcoin gamers could buy a single item for a nickle or dime, Liew said.

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They added other products to the line very quickly, determined not to be identified with a single item.

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And you will not believe how difficult it is to actually understand every single item in the store.

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