The EPA's threshold for safe exposure to PM 2.5 particles, as they're called, is 15 micrograms per cubic meter of air.

美国环保局的安全环境门槛是可吸入颗粒为PM 2.5，即每立方米空气中颗粒含量为15(译者：应该为25)微克。

youdao

Well I hope the guide's been helpful, if there's anything more you want to know, feel free to PM me or post here. Thanks for reading.

我希望这个攻略有用，想要了解更多可以联系我，感谢阅读。

youdao

The gallery is open Monday through Friday, 9 am to 6 pm.

美术馆的开放时间为周一到周五，上午9点到下午6点。

《柯林斯英汉双解大词典》

There will be a review session for those of you who care to come given by myself in 26-100 tomorrow night starting at 7 pm going until the last question is answered.

有一节复习课给那些关心的人,我亲自来上,明天晚上7点开始,这将持续到最后一个问题被解决。

麻省理工公开课 - 固态化学导论课程节选

It's a free music and art festival, it will be 11 am to 7 pm, all day and night.

这是一个免费的音乐艺术节，上午11点到晚上7点，一整天。

请记住我 - SpeakingMax英语口语达人

We do expect the majority of the students to tackle, as you'll see tonight when the PDFs go online at 7 PM, the so called standard edition of each problem set.

我们希望你们大部分能解决这些问题，你将会看到我们下午7点钟,会把PDF放到网上去，也就是每套问题的标准版本。

哈佛公开课 - 计算机科学课程节选

The Morbid Anatomy Museum is open Wednesday to Monday, 12 pm to 6 pm.

BBC: New York City��s most morbid museum

The Chinatown Night Market runs Friday to Sunday from 6 pm to 11 pm until 8 September.

BBC: Roll up for Vancouver��s revamped night market

Shadow business secretary John Denham and shadow transport secretary Maria Eagle have written to PM David Cameron urging him to review the decision.

BBC: Thameslink rail contract: Labour urges review