However,concerns about the stability of Greece , and other financially-troubled European countries, increased after the Standard and Poor's credit rating agency downgraded Greek bonds to speculative or "junk" status Tuesday.
VOA: standard.2010.04.28
and I asked you to give yourself a percentage rating relative to the rest of the class, then if everybody was accurate, or at least not systematically biased, the number should add up to 50%.
我要你相比于其他同学的表现,给自己一个百分数,如果大家都准确地评价自己,或者说大家都不偏心于自己,那么平均百分数应该是50%的。
So if you're working with cyanide in the lab as potassium cyanide or sodium cyanide, those are what are called p h s's, it's a rating for different kinds of chemicals.
因此如果你在实验室中,需要用到氰化物,比如氰化钾或者氰化钠,这就是所谓的,“P,H,S“,这是化学药品有害程度的一个级别。
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