O que significa Why might the following be on a knife-edge? A president? The economy? Top athlete? ?

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@keanakoski

I think you are trying to ask how to use the term ‘knife’s edge’ in regard to a President, the economy and a top athlete.

‘A knife’s edge’ conveys the idea that someone or something is on the verge of significant change. This could be good or bad change.

Examples: “The President’s re-election campaign is on the knife’s edge of total collapse when it was revealed today he had a drug problem while serving in office last year.”

“The gold medal athlete is on the knife’s edge of setting a new world record in swimming. She just needs to beat the Freestyle event by .03 seconds.”

Think of the edge of a knife. Look down it lengthwise and you see there is very little width if something was balanced on its edge. Kind of like standing at the edge of a cliff.