名詞 four:

1. the cardinal number that is the sum of three and one
   同義詞：4, IV, tetrad, quatern, quaternion, quaternary, quaternity, quartet, quadruplet, foursome, Little Joe

形容詞 four:

1. being one more than three
   同義詞：4, iv

1. This street is four times shorter than that one.
   這條街道比那條短四倍。
2. There are four wheels in a car.
   一輛汽車有四只輪子。
3. He arranged his speech under four main heads.
   他把發(fā)言內(nèi)容歸納成四個(gè)主要方面。
4. This line is four times as long as that one.
   這條線是那條線的四倍長。
5. Our cat has a litter of four kittens.
   我們家的貓一窩養(yǎng)了4只小貓。
6. After walking for four hours we were beginning to flag.
   步行了四個(gè)小時(shí)以后，我們開始累了。
7. Six minus two equals four.
   六減去二等于四。

four

n.（名詞）
The cardinal number equal to 3 + .
四：一基數(shù)詞，等于3加之和
The fourth in a set or sequence.
第四：一組或一列中的第四個(gè)
Something having four parts, units, or members, such as a musical quartet or a four-cylinder engine.
四個(gè)一組之物：四個(gè)（人或物）一組，如音樂四重奏，四缸發(fā)動(dòng)機(jī)等

<習(xí)慣用語>all fours
All four limbs of an animal or person:
四肢：人或動(dòng)物的四肢：
例句：
a baby crawling on all fours.
一個(gè)匍匐爬行的嬰兒

來源：
Middle English
中古英語
from Old English fôower * see k wetwer-
源自 古英語 fôower *參見 k wetwer-

【引伸】
four
adj.（形容詞）
pron.（代詞）