词根：-ann-

【词根含义】：年

【词根来源】：来源于拉丁语名词ann.us, ann.i, m(年)。

【同源单词】：annals, anniversary, annual, annuity, biannual

前缀：bi-

【词根含义】：两,二

【词根来源】：来源于拉丁语bi-。

【同源单词】：biannual, bicentennial, bicorn, bicycle, biennial

词根词缀：-al, -ial, -eal

【来源及含义】Latin: suffix; pertaining to, like, of the kind of, relating to, characterized by, belonging to; action of, process of

【同源单词】abacterial, abdominal, abdominal adhesion, abdominal aorta, abdominal aortic aneurysm, abdominal aortography

词根词缀：bi-, bin-, bino-, bis-

【来源及含义】Latin: two, twice, double, twofold; a number; it normally functions as a prefix

【相关描述】This bi- is used before s, c, or a vowel. Don't confuse this bi- with another one which means "life".

All words except biennial referring to periods of time and prefixed by bi- are potentially ambiguous. Since bi- can be taken to mean either "twice each" or "every two", a word like "biweekly" can be understood as "twice each week" or "every two weeks".

【同源单词】biacid, biangular, biannual, biannual, biarchy, biarticulate

词根词缀：-enni-, -ennial, -ennium

【来源及含义】Latin: year, years

【同源单词】aere perennius, amillennialism, annual, biannual, bicentennial, biennia