n.污染；污染物
Contamination can't be ruled out entirely. 污染是不能完全清除的。
Such contamination has been extensively studied. 人們對(duì)這種污染進(jìn)行了大量研究。
We believe any level of contamination is unacceptable. 我們認(rèn)為任何污染物都是不可接受的。
n.凈化；排除污染
