单词：slow sand filter bed
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But the HEPA filter for Olivers Vibe got dirty very quickly. And, it was not cleanableit was simply replaceable. When it turned filthy brown, Oliver went back to Target to buy a new filter. Oddly, Target sold the F15 belt for the Vibe, but not the fi
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From VOA Learning English, this is the Health Lifestyle report. In parts of India, it is not uncommon to see people wearing a mask over their nose and mouth. The capital, New Delhi, has some of the world's dirtiest air. The pollution was a call for a
2018年VOA慢速英语(一)月
Song：Who's Been Sleeping In My Bed Artist：Brosis Who's been sleeping in my bed? Ain't nobody sleeping in your bed,what you're talking about? I'm innocent,I didn't treat you bad girl, What you're talking about? What? what? Chorus: Who's been sleep
英语热力歌曲
By Tabinda Naeem Washington, D.C. 21 May 2007 Two years ago, the National Academy of Engineering established the Grainger Challenge Prize for Sustainability. This $1 million award was designed to challenge the world's scientists to develop a practica
2007年VOA标准英语（五月）