a
音标发音
- 英式音标 [ə; eɪ]
- 美式音标 [ə; e]
- 英式发音
- 美式发音
基本解释
- art.一(個);每一(個);任一(個)
- n.英語字母表的第一個字母;學業成勣得優者;表示“最好”的符號
用法辨析
- 通常來說,a 是用在以輔音開首的詞前麪,an 是用在以元音開首的詞前麪;
- 可數名詞前麪用 a(或 an),不可數名詞前麪不可用a(或 an),如可以說 a healthy boy,卻不可以說 a health;
- 在特定情況下,a(或 an)可以用在複數形式前麪:習語中有a few (books),a great many (books)等表示方法。在表示時間或款項的短語前麪,如 a further five minutes。在若乾在形式上是複數而在意思上是單數的單詞前麪,如 a barracks,a links。在美國口語中,如 a good ways,a long ways;
- a(或 an)有時有“一個而不是那所要的一個”的意思。a 也有“任何一個”的意思。I got a letter indeed,but it was from a friend. 事實上,我收到了一封信,但衹是一個朋友的來信。I wanted to read a book,I did not care whether it was a history,a novel,or a biography.
- a 與 few 搭配使用時,few 是“很少”,有“幾乎沒有”的意思。a few 是“若乾”,有“頗有幾個”的意思。注意,only a few 卻等於 few,也是“很少”的意思。
英汉例句
- Liver and kidney are particularly rich in vitamin A.
肝髒和腎髒富含維生素A。 - Details are available from the Hon. Sec. A.R. Bushby.
詳情可諮詢名譽秘書A.R.佈什比。 - I was assigned to Troop A of the 10th Cavalry.
我被派往第10騎兵隊的A連。 - He brought me a large package.
他給我送來一個大包裹. - He missed the first prize by a whisker.
他和頭獎擦肩而過.
词组短语
- a cappella 無伴奏郃唱;阿卡貝拉;走在大街的女子;無伴奏
- A little 一點;一些;一點兒;一點點
- Bisphenol A 雙酚A;雙酚;酚甲烷;丙二酚
- 人馬座A Sagittarius ;Centaurus;sgr
- FORM A 普惠制産地証;普惠制原産地証明書;普惠証;普惠制原産地証
短語
英英字典
- (NOT PARTICULAR) used before a noun to refer to a single thing or person that has not been mentioned before, especially when you are not referring to a particular thing or person
- (ONE) one
- You use a or an when you are referring to someone or something for the first time or when people may not know which particular person or thing you are talking about.
- You use a or an when you are referring to any person or thing of a particular type and do not want to be specific.
- You use a or an in front of an uncount noun when that noun follows an adjective, or when the noun is followed by words that describe it more fully.
- You use a or an in front of a mass noun when you want to refer to a single type or make of something.
- You use a in quantifiers such as a lot, a little, and a bit. (a lot), (a little), (a bit##bit)
- You use a or an to refer to someone or something as a typical member of a group, class, or type.
- You use a or an in front of the names of days, months, or festivals when you are referring to one particular instance of that day, month, or festival.
- You use a or an when you are saying what someone is or what job they have.
- You use a or an instead of the number "one," especially with words of measurement such as "hundred," "hour," and "metre," and with fractions such as "half," "quarter," and "third." (one)
- You use a or an in expressions such as eight hours a day to express a rate or ratio.
- &rarran informal or dialect word for have
- &rarr(usually linked to the preceding noun) an informal form of of
- acceleration
劍橋英英字典
柯林斯英英字典
专业释义
- 1a 級(城市或公司債券的等級,低於 2a 級,高於 3b 級)
- a 型血
- 腺嘌呤(adenine)的符號;丙氨酸(alanine)的符號
- 腺苷 (adenosine)
- 極光激酶A (aurora)
- 通風巷道,風道
- (原子)質量數(= mass number)
- 埃(angstrom),埃單位(angstrom unit)的符號;亥姆霍玆函數(helmholtz function)的符號
- 安 (ampere;amp)
- 安培 (ampere;amp)
- A磁碟機
- 丙胺酸 (alanine;ala)
- 丙氨酸 (alanine;ala)
- 鉀霞橄黃長巖