词根词缀：pro-, por-, pur-

【来源及含义】Greek > Latin: a prefix signifying before; forward, forth; for, in favor of; in front of; in place of, on behalf of; according to; as, to place before; to go before or forward, to throw forward

【相关词根词缀】 Related before-word units: ante-; antero-; anti-; pre-.

【同源单词】portend, portent, portentous, portentously, portentousness, pro