slight grade

基本解释

And the content of subnitrate in all vegetable products was in slight pollution (grade 1).
亚硝酸盐含量均处于轻度污染（1级）；
And the synthetic index of soil pollution was 1.3, which was three grade slight pollution.
调查区域土壤的综合污染指数为1 .3，达3级为轻度污染。
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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.
级和AA级木材的区别在于： A级木材存在一些颜色的轻微变化，木材结构的均匀度有一些变化。
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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