oughtyoudaoicibaDictYouDict[ought 词源字典]
ought: [OE] Ought began life as the past tense of owe, but the two have diverged widely over the centuries. The Old English ancestor of owe was āgan, and its past form was āhte. This originally shared all the meanings of its parent verb, of course, and continued to do so well into the 17th century (‘He said this other day, you ought him a thousand pound’, Shakespeare, 1 Henry IV 1596). Indeed, it survived dialectally until comparatively recently. But steadily since the 1600s its role as a quasi-modal auxiliary verb, denoting ‘obligation’, has come to the fore.
=> owe[ought etymology, ought origin, 英语词源]
ought (v.)youdaoicibaDictYouDict
Old English ahte "owned, possessed," past tense of agan "to own, possess, owe" (see owe). As a past tense of owe, it shared in that word's evolution and meant at times in Middle English "possessed" and "under obligation to pay." It has been detached from owe since 17c., though he aught me ten pounds is recorded as active in East Anglian dialect from c. 1825. As an auxiliary verb expressing duty or obligation (late 12c., the main modern use), it represents the past subjunctive.
ought (n.)youdaoicibaDictYouDict
"zero, cipher," 1844, probably a misdivision of a nought (see nought; for misdivision, see N); meaning probably influenced by aught "anything."