In this election at this defining moment change has come to America.

在这个决定性的时候，变革来到了美国。

youdao

But on this January night - at this defining moment in history - you have done what the cynics said we couldn't do.

但在这个一月的夜晚，在这个书写历史的时刻，你们做到了那些愤世嫉俗的人断言我们做不到的事。

youdao

Tonight, because of what we did on this date, in this election, at this defining moment, change has come to America.

今夜，因为我们在这场竞选中，在这个地方，在此时此刻所做的一切，改变已经来到美国。

youdao

"I don't look at this moment as the defining end to my relationship with the game of basketball,".

VOA: standard.2009.12.24

So at this defining moment in history let us renew our special relationship for our generation and our times.

BBC: In full: Brown's speech to Congress

It's been a long time coming, but tonight, because of what we did on this day, in this election, at this defining moment, change has come to America.

NPR: Obama Must Manage Great Expectations

Because we all agree that at this defining moment in history -- a moment when we're facing two wars, an economy in turmoil, a planet in peril -- we can't afford to give John McCain the chance to serve out George Bush's third term.

CNN: Clinton fights on as focus turns to superdelegates