The war continued for an eternity.

那场战争持续了极长的时间。

《柯林斯英汉双解大词典》

In heaven we will enjoy God's family forever, but first we have some tough work to do here on earth to prepare ourselves for an eternity of loving.

在天堂我们永远享有神的家，但首先我们在世上却需要努力为那永恒的爱准备自己。

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To end this historic conflict, both sides must be historically bold, because if each waits stubbornly for the other to act first, this will go on and be waiting for an eternity."

VOA: standard.2010.03.11

Yet even there, when I imagine an eternity of thinking about math--or for that matter, an eternity of thinking about philosophy, which I obviously like even more than math-- the prospect seems an unattractive one.

即使如此，当我想到让我永远,思考数学问题，或者说，让我永远思考哲学问题，显然和数学相比，我更钟情于它-,但这个提议也变得无趣。

耶鲁公开课 - 死亡课程节选

The movie dribbles on for an eternity, sometimes intelligently and companionably, sometimes vacuously.

NEWYORKER: Eat Pray Love

The latest of these, which has been filling the blogosphere with rumors for an eternity now, is the iPhone 5, which it looks like the company will be unveiling on Sept. 12.

FORBES: iPhone 5: Apple Needs to Make This One Count

For instance, while some might believe that it must have felt like an eternity for Jeter to accumulate his final six hits for 3, 000, Cal Ripken, Jr. had to wait an entire offseason in order to collect the final hits for 3, 000.

FORBES: An Unconventional Look At Derek Jeter's Journey To 3,000 Hits