age out 【非正式用語】

To reach an age, 18 or 21 years, for example, at which one is no longer eligible for certain special services, such as education or protection, from the state.

法定年齡：到達一定年齡，例如18歲或21歲，不再享受國家的諸如教育或保護的某些特殊照顧

act (或 be) one's age

[usa. in imperative]behave in a manner appropriate to someone of one's age and not to someone much younger

行為與年齡相稱

come of age

(of a person) reach adult status (in UK law at 18, formerly 21)

（人）成年（英國法律現規(guī)定18歲成年，原為21歲）

of an age

old enough to be able or expected to do something

到了…的年齡

the sons are of an age to marry.

兒子們到了結婚的年齡。

(of two or more people or things) of a similar age

（兩者，多人，多物）年齡近似的

the children all seemed of an age.

孩子們看起來差不多大。