词根：-val-

【词根含义】：强壮;价值

【词根来源】：来源于拉丁语动词valeo, valere, valui, valitus(强壮,价值)。

【同源单词】：avail, available, countervail, devaluate, devaluation

前缀：pre-

【词根含义】：前,先

【词根来源】：来源于拉丁语prae。

【同源单词】：precaution, precede, precedent, preceding, precise

词根词缀：pre-, prae-

【来源及含义】Latin: before [both in time and place]

【相关描述】The prefix prae- can actually be substituted for pre- because both of them are different spellings for the same prefix meaning "before".

【相关词根词缀】 Related before-word units: ante-; antero-; anti-; pro-. Related "time" units: aevum, evum; archaeo-, archeo-; Calendars; chrono-; horo-; Quotes: Time; tempo-.

【同源单词】preacquaint, preacquaintance, preagonal, pre-agricultural, preamble, preambular

词根词缀：valid-, val-, vale-, -vail, -valent, -valence

【来源及含义】Latin: valere, to be strong, to be well, to be worth; strong; power, strength; and "fare well" [go with strength]

【同源单词】Ab abusu ad usum non valet consequentia, Ab actu ad posse valet illatio, ad valorem, Aeternum vale, ambivalence, ambivalent