词根词缀：quinqu-, quinqua-, quinque-

【来源及含义】Latin: five, fifth; a word element for number 5

【同源单词】quinquagenarian, quinquagenary, Quinquagesima, quinquagesimal, quinquangular, quinquefarious

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