词根词缀：dat-, dos-, dot-, dow-, don-, dit-

【来源及含义】Greek + Latin: dare, to give, a giving, given; a gift; to grant, to offer

【相关词根词缀】 Another term used for medical dosage can be seen at this posology page.

【同源单词】a datu, a die datus, air dose, anecdote, antidotal therapy, antidote

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