How long ago did you buy it?

这东西你是多久以前买的？

《牛津词典》

youdao

We'll go to a bookstore and buy it.

我们去书店把它买下来。

youdao

"Part of the issue with the finance stuff,I think, is if people really understood it, they wouldn't buy it."

VOA: special.2010.04.30

There's no company that's making smallpox vaccine anymore because there's no reason to make smallpox vaccine, because nobody would buy it, right?

没有公司还生产天花疫苗,因为没有人购买天花疫苗,因此早就没有理由继续生产它了,对吧

耶鲁公开课 - 生物医学工程探索课程节选

No. He would give it to me for free. I don't need to buy it.

没有。他会免费送给我的。我不需要买。

我喜欢的建筑物 - SpeakingMax英语口语达人

Do you need or want it enough to buy it for your own use.

FORBES: 5 Tips For Women Investing In Entrepreneurs Via Crowdfunding

In a marketplace you can find what you want, look it over, and buy it.

FORBES: How to Fix Apps Marketplaces

Over half of Indonesia's cement goes to rural areas where people buy it to build houses.

CNN: 'THE PEOPLE'S ASPIRATION'