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Sterling completes the trick (yo-yo), flashing a winning smile, and applause erupts from the audience.

What does "flashing a winning smile" refer to? Is it "showing briefly and quickly a winning smile?" Thanks.
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Hi Angliholic

To me, the use of 'flashing' suggests lots of brilliant whiteness (i.e. lots of teeth), and therefore Sterling's smile is a very big and happy one.
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YankeeHi Angliholic

To me, the use of 'flashing' suggests lots of brilliant whiteness (i.e. lots of teeth), and therefore Sterling's smile is a very big and happy one.

Thanks, Amy.

I like your interpretation, but I wonder why it suggests to you lots of brilliant whiteness ( lots of teeth?) Would you shed more light?
Hi Angliholic

A smile can also be smaller, with no teeth showing. Maybe the author wanted to suggest both ideas -- both 'quick' and 'white'. A flash of lightning, for example, is usually fast, but it is also often described as 'blinding' and 'white'. Possibly the author wanted to suggest that a "blindingly" big smile appeared instantly. Emotion: big smile
Thanks, Amy.

Roger!
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