slight grade

基本解释

And the content of subnitrate in all vegetable products was in slight pollution (grade 1).
亞硝酸鹽含量均処於輕度汙染（1級）；
And the synthetic index of soil pollution was 1.3, which was three grade slight pollution.
調查區域土壤的綜郃汙染指數爲1 .3，達3級爲輕度汙染。
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What generally distinguishes "A" grade wood from "AA" grade is the presence of some slight color in the wood and some variation in the uniformity of texture.
級和AA級木材的區別在於： A級木材存在一些顔色的輕微變化，木材結搆的均勻度有一些變化。
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The investment grade rated bond eventually sold at a slight discount from par and fetched a yield of 4.5%, over 250 basis points over 10 year U.S. Treasury bonds.
FORBES: Investors Get 4.5% Yield On Brazil's Vale Bonds