塑胶中的化学物质 (1)

科学60秒:X光——透射生活的美好

X-rays are so common today you probably never stop to think about them. They help check a broken wrist, a sprained ankle, the state of our teeth. But a little more than a century ago, x-ray machi

告别寂静的春天

故事Rachel Carson was a scientist and a bird watcher. She noticed, in the late '50s, the gradual disappearance of some birds, and linked it to our use of 1)pesticides. She wrote a book about her ...

鼓起勇气

Summon up Courage:鼓起勇气docile：温顺的ditch沟，壕沟There were two men who both decided to get a horse for riding .One man found a red horse with much spirit while the other chose one more docil...

长寿之道：对未来充满希望 (1)

Hints:Hilary Tindle Pittsburgh PennsylvaniaHere is a good reason to be hopeful about the future: it might help you stay alive. Findings from a new study were presented at a recent meeting of the...