词根词缀：oper-, opus

【来源及含义】Latin: work

【相关词根词缀】 Cross references related to "work, toil" word families: argo-; ergasio-; ergo-; labor-; pono-; urg-.

【同源单词】co-operate, co-operation, co-operative, co-operativeness, ignioperation, inoperable

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