It has happened before.

这在以前就发生过。

youdao

It has happened before.

以前也发生过。

youdao

"Historically it has happened before," the former United player said.

这位前曼联球员说：“历史上这样的事情也发生过，球队因此而获益。”

youdao

"It is a significant find within Sierra Leone because it has never happened before in Sierra Leone."

VOA: standard.2010.04.22

It's not taking place in this life, so it has to have happened before.

既然不是这辈子发生的,那么就肯定是以前发生的

耶鲁公开课 - 死亡课程节选

It has happened before under more dire circumstances, after the herd all headed for the exit.

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If this is a cause for concern, maybe there is solace in knowing that it has happened before.

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It has happened before: the fairly free world economy of the late 19th century was riddled with protectionism by the 1930s.

ECONOMIST: World trade