e-: the later Romans evidently found words beginning in sc-, sp-, st- difficult or unpleasant to pronounce; in Late Latin forms begin to emerge in i- (such as ispatium, ispiritu), and from 5c. this shifted to e-. 单词有：eschew（避开），especial（特别的），espouse（支持，赞成），establish（建立），estate（不动产）
neg：表示 no 的意思，单词有：abnegation（放弃，拒绝），negatron（负电子），neglect（疏忽），renege（食言，毁约），necessary（必须的，没有离开的），nefarious（恶毒的，极坏的，不正义的）
cad, cas, cid：表示 to fall 的意思，单词有：decadence（堕落，颓废），accident（意外事件），cadaver（尸体），cadaverous（像尸体般的），cadence（抑扬，调子，节奏），cascade（小瀑布），deciduous（每年落叶的）。indeciduous（常绿的，不落叶的），casual（便装的，偶然的），casualty（伤亡人员），coincide（一致，一起下落），incident（偶然事件），incidence（发生率），incidental（附带事件，偶然的）
英语语法概念：copula
In linguistics, a copula (plural: copulas or copulae; abbreviated cop) is a term for a word that links the subject of a sentence to a subject complement, such as the word is in the sentence “The sky is blue.” The word copula derives from the Latin noun for a “link” or “tie” that connects two different things.
A copula is often a verb or a verb-like word, though this is not universally the case. A verb that is a copula is sometimes called a copulative or copular verb. In English primary education grammar courses, a copula is often called a linking verb.
Most languages have one main copula, although some (like Spanish, Portuguese and Thai) have more than one, and some have none. In the case of English, this is the verb “to be”. While the term copula is generally used to refer to such principal forms, it may also be used to refer to some other verbs with similar functions, like become, get, feel and seem in English (these may also be called “semi-copulas” or “pseudo-copulas”).
成为单词的人名：Samuel Maverick
Samuel Augustus Maverick (July 23, 1803 — September 2, 1870) was a Texas lawyer, politician, land baron and signer of the Texas Declaration of Independence. His name is the source of the term “maverick,” first cited in 1867, which means “independently minded.” Various accounts of the origins of the term held that Maverick came to be considered independently minded by his fellow ranchers because he refused to brand his cattle, though it might have instead reflected a lack of interest in ranching. Unbranded cattle which were not part of the herd came to be labeled “mavericks”.
maverick：[‘mæv(ə)rɪk] n.特立独行者，独行侠；没打烙印的牲畜adj.特立独行的，不按常规的；未打烙印的（牲畜）
修辞概念：metaphor
A metaphor is a figure of speech that, for rhetorical effect, directly refers to one thing by mentioning another. It may provide clarity or identify hidden similarities between two ideas. Antithesis, hyperbole, metonymy and simile are all types of metaphor.
