To figure out even what this thing is, let alone how to use it properly. So, you know, I'm sympathetic.

就连认出这是什么东西（都很困难），更别说正确应用它了，所以我很同情这点。

经常犯的失误 - SpeakingMax英语口语达人

I barely know how to use a cell phone let alone a computer, you know,

我勉强会用手机，更不要说电脑了，你知道，

现在的孩子好可怕 - SpeakingMax英语口语达人

Like Lisette was going to remember this name, let alone use it.

NEWYORKER: I.D.

Best Buy : People can hardly keep up with the newest technological equipment, let alone how to hook it up and use it.

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But many companies do not yet have an energy strategy, let alone broader sustainability strategies to manage the use of water, land, and other resources.

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