词根词缀：ad-

【来源及含义】Latin: prefix; to, toward, a direction toward, addition to, near, at; and changes to: ac-, af-, ag-, al-, an-, ap-, aq-, ar-, as-, at- when ad- is combined with certain words that begin with the letters c, f, g, l, n, p, q, r, s, and t

【相关描述】The form ad- appears in this form before a vowel and before the consonants d, h, j, m, and v. It is simplified to a- before sc, sp and st.

Before c, f, g, l, n, p, q, r, s, and t; ad- is changed to ac-, af-, ag-, al-, an-, ap-, aq-, ar-, as-, and at-.

In other words, the d of ad usually changes into the same letter as the first letter of the following root or word when it is a consonant: ad-fix becomes affix, and ad-sign becomes assign; therefore, making a double consonant.

Another example includes: attract as with ad-tract (drawn towards); so it has a double t. On the other hand when ad- precedes a vowel, as with adapt, it is simply ad-apt, with one d. For the same reason, there is only one d in adore and adumbrate, because ad- has combined with orare and umbra each of which starts with a vowel.

So, remember: since these Latin words begin with vowels and not consonants, the d of ad does not double as shown in the previous examples.

【同源单词】a capite ad calcem, Ab ovo usque ad mala, Ab uno ad omnes, Abiit ad majores, abjure, accede

词根词缀：bene-, ben-, beni-

【来源及含义】Latin: good, well

【同源单词】Ab officio et beneficio, Ad captandam benevolentiam, Ad vindictam tardus, Bene tenax, Bene vale, benedicence

词根词缀：dic-, dict-

【来源及含义】Latin: talk, speak, say, tell, declare; to proclaim; to indicate

【相关词根词缀】Cross references of word families related directly, or indirectly, to: "talk, speak, speech; words, language; tongue, etc.": cit-; clam-; fa-; -farious; glosso-; glotto-; lalo-; linguo-; locu-; logo-; loqu-; mythico-; -ology; ora-; -phasia; -phemia; phon-; phras-; Quotes: Language,Part 1; Quotes: Language, Part 2; Quotes: Language, Part 3; serm-; tongue; voc-.

【同源单词】abdicable, abdicant, abdicant, abdicate, abdicate, abdication

词根词缀：tard-

【来源及含义】Latin: slow; sluggish

【相关词根词缀】 Cross references directly, or partly, involving "slow, slowness, slow of, sluggish": dys-; lent-.

【同源单词】Ad vindictam tardus, aquitard, mental retardation, psychomotor retardation, psychosocial retardation, retard

词根词缀：vin-

【来源及含义】Latin: force

【同源单词】Ad vindictam tardus, Deo vindice, vindicate, vindication, vindication, vindicator