class 含义广泛，指人或物按优劣划分的等级，也指学校中的年级或班级。
degree 指程度、范围不同，社会地位的高低。也可指形容词或副词的级。
grade 指按地位或优劣划分的等级，既可指人又可指物。
rank 指人在社会中的地位或等级，尤指军队中的军衔。
参考例句
1. His books were ranked tidily on the bookshelf. 他的书籍整整齐齐地排列在书架上。
2. I rank her among the country 's best writers. 我认为她可属全国最优秀作家之列。
3. Ordering in a series or according to rank or time. 按照系列、等级或时间进行排序的过程或方法。
英英解释
n.
1. a row or line of people (especially soldiers or police) standing abreast of one another
2. relative status
3. the ordinary members of an organization (such as the enlisted soldiers of an army)
4. position in a social hierarchy
5. the body of members of an organization or group v.
1. take or have a position relative to others
2. assign a rank or rating to
3. take precedence or surpass others in rank adj.
1. very fertile; producing profuse growth
2. very offensive in smell or taste
3. conspicuously and outrageously bad or reprehensible
4. complete and without restriction or qualification; sometimes used informally as intensifiers
5. growing profusely
