名詞 lifetime:

1. the period during which something is functional (as between birth and death)
   同義詞：life, life-time, lifespan

1. Could you reconcile yourself to a lifetime of unemployment?
   你能甘心一輩子失業(yè)嗎?
2. The government is unlikely to get the bill through within (the lifetime of) this Parliament.
   政府不大可能在本屆國(guó)會(huì)(會(huì)期)內(nèi)通過(guò)該項(xiàng)法案。
3. He could not but look up to the sky and sigh deeply when his lifetime of frustrations passed through his mind.
   想起自己坎坷的一生，他不由仰天長(zhǎng)嘆。
4. He is a legend in his lifetime for his scientific discoveries.
   他的科學(xué)發(fā)現(xiàn)使他一生成為傳奇人物。
5. It's a once in a lifetime chance.
   這是一生難得的機(jī)會(huì)。
6. A lifetime guarantee; lifetime membership.
   終身保障; 終身會(huì)員資格
7. I doubt if there will be a female president in this country in my lifetime.
   我懷疑在我有生之年這個(gè)國(guó)家會(huì)不會(huì)出現(xiàn)一位女總統(tǒng)。

life.time

n.（名詞）
The period of time during which an individual is alive.
一生：一個(gè)人生存的一段時(shí)間
The period of time during which property, an object, a process, or a phenomenon exists or functions.
存在期，有效期：某種性質(zhì)、物體、過(guò)程或現(xiàn)象存在或起作用的一段時(shí)間
n.attributive.（定語(yǔ)名詞）
Often used to modify another noun:
終生：經(jīng)常用來(lái)修飾另一個(gè)名詞：
例句：
a lifetime guarantee; lifetime membership.
終身保障；終身會(huì)員資格