词根：-grad-, -gress-

【词根含义】：步,级

【词根来源】：来源于拉丁语名词gradus(步)和拉丁语动词gradior, gradi, gressus, sum(步行)。

【同源单词】：centigrade, degrade, downgrade, gradation, grade

前缀：e-, ex-

【词根含义】：出,向外;向上

【词根来源】：e-用在b, c, d, g, j, l, m, n, r, v前;ex-用在s前时,s常省略。来源于拉丁语前缀ex-。

【同源单词】：edit, edition, editor, editorial, educate

词根词缀：ex-, e-, ef-

【来源及含义】Latin: a prefix occurring in words of Latin origin used in the senses: out, out of, from; upward; completely, entirely; to remove from, deprive of; without; former [said of previous holders of office or dignity]

【相关描述】Before f, ex- becomes ef-; before all voiced consonants (as b, d, g, etc.) ex- becomes e-.

【同源单词】e pluribus unum, educate, educe, efface, effacement, effete

词根词缀：grad-, -grade, -gred, -gree, -gress

【来源及含义】Latin: walk, step, take steps, move around; walking or stepping

【同源单词】ad eundem gradum, aggradation, aggression, aggressive, aggressively, aggressiveness