pledge: [14] Pledge comes via Old French plege from late Latin plebium, a derivative of the verb plebīre ‘pledge’. This was probably borrowed from Frankish *plegan ‘guarantee’, a derivative of the same Germanic base as produced English plight ‘pledge’ [OE] (as in ‘plight one’s troth’) and German pflicht ‘duty’. => plight
pledge (v.)
c. 1400, "to promise" (something to someone), "to give over as security for repayment," also "promise faith to," from pledge (n.) and from Old French plegier, from plege (n.). From mid-15c. as "to stand surety for, be responsible for;" late 15c. as "to mortgage." Meaning "put (someone) under oath" is from 1570s; sense of "to solemnly promise or guarantee" is from 1590s, as is sense "to drink a toast." Related: Pledged; pledging.
pledge (n.)
mid-14c., "surety, bail," from Old French plege (Modern French pleige) "hostage, security, bail," probably from Frankish *plegan "to guarantee," from *pleg-, a West Germanic root meaning "have responsibility for" (cognates: Old Saxon plegan "vouch for," Middle Dutch plien "to answer for, guarantee," Old High German pflegan "to care for, be accustomed to," Old English pleon "to risk the loss of, expose to danger;" see plight (v.)).
Meaning "allegiance vow attested by drinking with another" is from 1630s. Sense of "solemn promise" first recorded 1814, though this notion is from 16c. in the verb. Weekley notes the "curious contradiction" in pledge (v.) "to toast with a drink" (1540s) and pledge (n.) "the vow to abstain from drinking" (1833). Meaning "student who has agreed to join a fraternity or sorority" dates from 1901.
例文
1. His tax-cutting pledge brought a delirious crowd to their feet.
彼の減税の約束は興奮した人々を喜ばせた。
2.In the treaty both sides pledge to respect human rights.
双方は、人権を尊重することを条約で約束している。
3.I pledge that by next year we will have the problem solved.
来年までにこの問題を解決することを保証します。
4.The agreement includes a pledge of non-aggression.