名詞 one:

1. the smallest whole number or a numeral representing this number
   同義詞：1, I, ace, single, unity
2. a single person or thing

形容詞 one:

1. used of a single unit or thing; not two or more
   同義詞：1, i, ane
2. having the indivisible character of a unit
   同義詞：unitary
3. of the same kind or quality
4. used informally as an intensifier
5. indefinite in time or position
6. being a single entity made by combining separate components
7. eminent beyond or above comparison
   同義詞：matchless, nonpareil, one and only, peerless, unmatched, unmatchable, unrivaled, unrivalled

1. One should do his best for the cause of world peace.
   一個人應(yīng)該為世界和平事業(yè)盡最大努力。
2. A person has one head and one neck.
   每人都有一個頭，一個脖子。
3. If only problems would come one at a time!
   要是問題一次只發(fā)生一個該多好！

one

adj.（形容詞）
Being a single entity, unit, object, or living being; not two or more.
一個的，單一的：是一個實體、單元、物體或生物的；而不是兩個或者更多
Characterized by unity; undivided:
同一的，整體的：以整體性為特點的，不可分的：
例句：
They spoke with one voice.
他們異口同聲

Of the same kind or quality:
同一種類的，同一性質(zhì)的：
例句：
two animals of one species.
同一種類的兩個動物

Forming a single entity of two or more components:
單一實體的：由兩個或更多個要素形成的一個單一實體：
例句：
three chemicals combining into one solution.
三種化合物溶成一種溶液

Being a single member or element of a group, category, or kind:
一個成員的，一個要素的：成為一組、一個部門或一個種類中的一員或一個要素的：
例句：
I`m just one player on the team.
我只是這個球隊中的一名球員

Being a single thing in contrast with or relation to another or others of its kind:
（與其它同類東西）相同的：與同類中另一個或其它的相對或相關(guān)的一種事物：
例句：
One day is just like the next.
每天都一樣

Occurring or existing as something indefinite, as in time or position:
某一（時間或事物）：在某一不確定的時間發(fā)生或出現(xiàn)的，如在時間或位置上：
例句：
He will come one day.
他總有一天會來

Occurring or existing as something particular but unspecified, as in time past:
（過去的時間）某一特定的：如某特殊事物的出現(xiàn)或存在，如過去的時間：
例句：
late one evening.
某一個深

Informal Used as an intensive:
【非正式用語】 用來加強語氣：
例句：
That is one fine dog.
這是一條不錯的狗

Being the only individual of a specified or implied kind:
特定的：是特定或暗指的種類中的唯一個體：
例句：
the one person I could marry; the one horse that can win this race.
我唯一愿嫁的人；唯一能贏得這次比賽的馬

n.（名詞）
The cardinal number, represented by the symbol , designating the first such unit in a series.
一：基數(shù)，用符號表示，代表一系列中這樣的單元中的第一個
A single person or thing; a unit:
一個：一個人或物，一個單元：
例句：
This is the one I like best.
這是我最喜歡的一個

pron.（代詞）
An indefinitely specified individual:
某人：
例句：
She visited one of her cousins.
她去拜訪了一位表親

An unspecified individual; anyone:
未指明的人；任何一個人：
例句：
.The older one grows the more one likes indecency.(Virginia Woolf)
.人愈老愈喜歡粗鄙的言行.(弗吉尼亞·沃爾夫)

<習慣用語>at one
In accord or unity.
一致，合力
one and all
Everyone.
每個人，全體
one by one
Individually in succession.
一個接一個
來源：
Middle English on
中古英語 on
from Old English 3n * see oi-no-
源自 古英語 3n *參見 oi-no-

When constructions headed byone appear as the subject of a sentence or relative clause, there may be a question as to whether the verb should be singular or plural.Such a construction is exemplified in the sentenceOne of every ten rotors was found defective. Although the pluralwere is sometimes used in such sentences, an earlier survey found that the singular was preferred by a large majority of the Usage Panel. ·Another problem is raised by constructions such asone of those people who or its variants. In the sentenceThe defeat turned out to be one of the most costly blows that were ever inflicted on our forces, most grammarians would hold that the pluralwere is correct, in as much as the subject of the verb is the plural nounblows. However, constructions of this sort are often used with a singular verb even by the best writers.Note also that when the phrase containingone is introduced by the definite article, the verb in the relative clause must be singular:
當以one 開頭的結(jié)構(gòu)作為一個句子或關(guān)系從句的主語出現(xiàn)時， 就出現(xiàn)動詞用單數(shù)還是復數(shù)的問題，如用在句子每十個轉(zhuǎn)子中有一個為次品 中的這種結(jié)構(gòu)。 雖然復數(shù)were 有時用在這種句子中， 但在一次早期的調(diào)查發(fā)現(xiàn)用法專題使用小組的大部分成員更傾向于用單數(shù)。另一個問題是由象one of those people who 這樣的結(jié)構(gòu)及其變化引起的。 在句子The defeat turned out to be one of the most costly blows that were ever inflicted on our forces, 中, 大多數(shù)語法學家主張用復數(shù)were 是正確的， 以及主要是由于動詞的主語是復數(shù)名詞blow 所致。 然而，這種結(jié)構(gòu)常與單數(shù)動詞連用，甚至被很有聲望的作家采用。也要注意當包含one 的短語被定冠詞限制時， 相關(guān)的從句中的動詞一定要用單數(shù)：
例句：
He is the only one of the students who has (not have ) already taken Latin. See Usage Note at he
他是這些學生中唯一一個（不用 have ) 曾學過拉丁語的人。 參見 he