three: [OE] Three goes back to a prehistoric Indo- European *trejes, which also produced Greek treis, Latin trēs, Russian tri, Sanskrit tráyas, etc. Its Germanic descendant was *thrijiz, which has evolved into German drei, Dutch drie, Swedish and Danish tre, and English three. Amongst three’s many relations in English are treble, trellis [14] (etymologically something made from ‘three threads’), trinity, trio [18], triple, tripod [17] (etymologically something with ‘three feet’), trivial and possibly also travail and tribe. => drill, testament, third, travail, treble, trellis, tribe, trinity, trio, triple, tripod, trivet, trivial
three (adj.)
Old English treo, fem. and neuter (masc. tri, trie), from Proto-Germanic *thrijiz (cognates: Old Saxon thria, Old Frisian thre, Middle Dutch and Dutch drie, Old High German dri, German drei, Old Norse trir, Danish tre), from nominative plural of PIE root *trei- "three" (cognates: Sanskrit trayas, Avestan thri, Greek treis, Latin tres, Lithuanian trys, Old Church Slavonic trye, Irish and Welsh tri "three").
3-D first attested 1952, abbreviation of three-dimensional (1878). Three-piece suit is recorded from 1909. Three cheers for ______ is recorded from 1751. Three-martini lunch is attested from 1972. Three-ring circus first recorded 1898. Three-sixty "complete turnaround" is from 1927, originally among aviators, in reference to the number of degrees in a full circle. Three musketeers translates French les trois mousquetaires, title of the 1844 novel by Alexandre Dumas père.
例文
1. Three plus six makes nine.
3プラス6は9.（注意、この文のplusは前置詞で、plussixは前置詞句で、 three の定語を作るので、動詞はmakesで、makeを使わない）。
2. Three hundred million dollars will be nothing like enough.
3億ドルでは十分ではありません。
3.After a three -weekend courtship，Pamela accepted Randolph 's proposal of marriage.3週末の追求を経て、パメラはルドルフのプロポーズを受けた。
4. Three prisoners were sharing one small cell 3 metres by 2 metres.
3人の囚人が長さ2メートルの小さな牢屋に閉じ込められている。
5.The three parties will meet next month to work out remaining differences.