• aux. 應該，應當；大概
• vi. 應該，應當；大概

來自古英語ahte,擁有的，所有的，來自agan的過去分詞，擁有，所有，詞源同own,owe.后詞義由擁有的引申為有義務去支付或償還，并最終在語法上演變成虛擬情態動詞。

ought

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 (v.)

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.)

"zero, cipher," 1844, probably a misdivision of a nought (see nought; for misdivision, see N); meaning probably influenced by aught "anything."

1. The money to build the power station ought to have been sufficient.

建設電站的資金本該足夠了。

來自柯林斯例句

2. I think you ought to give football a rest for a time.

我認為你應該暫時停止踢足球。

來自柯林斯例句

3. You know, we really ought to get another car.

要知道，我們真的應該換一輛車了。

來自柯林斯例句

4. I felt I ought to show my face at her father's funeral.

我覺得我應該去參加她父親的葬禮。

來自柯林斯例句

5. You ought to be ashamed of yourselves. You've created this problem.

你們應該感到慚愧，都是你們惹的禍。

來自柯林斯例句