分级的英文：
classification
grade
graduated
Outline
ratings

参考例句：

trackage classified by speed
按速度分级的(铁路)线路

A grade depending on the results of the final exam.
分级由期终考试的结果而定.

A boxer in a subcategory of the heavyweight division,having an upper weight limit set at190pounds(86kilograms.
次重量级拳击手重量级中拳击手的一个分级，该级别的体重上限为190镑(86公斤)

The principle of rewarding on level basis
分级奖励的原则。

Secondary School Placement
中等学校分级费

With Content Advisor, you can control access to Content Advisor settings.
使用分级审查，您可以控制访问分级审查设置。

Countability and gradability
可数性与分级定度

To turn on Content Advisor and set limits
启用分级审查并设置限制

Grade children according to age.
将孩子依年令分级。

Once its impurities had settled, the oil could be graded.
一旦杂质沉淀下去，油就可以分级了。

classification是什么意思：
n. 分类；等级

This kind of classification is not exhaustive.
这种分类法并不是包罗无遗的。

To determine the taxonomic classification of(an organism.
确定(有机体的)类别等级

They defy accurate classification at present.
这使目前的正确分类有困难。

grade是什么意思：
n. 年级；阶段；等级
v. 将…按级别分类；给…批分数，改作业；混合

longitudinal grade
纵坡度

There are lots of jobs in junior grades.
初级阶段有很多工作要做。

Red grades into pink.
红色逐渐变成粉红色。

graduated是什么意思：
adj. 毕业了的；标有刻度的；分等级的，分层次的

linear graduation
线性刻度

vernier graduation
游标刻度

She is a graduate student in literature.
她是个念文学的研究生。