Final answer:
The snow on the cherry is the best symbol for something that goes by too quickly in the given excerpt.
Step-by-step explanation:
The best symbol for something that goes by too quickly in the given excerpt is The snow on the cherry. The line 'To see the cherry hung with snow' suggests that the cherry blossoms in bloom, represented by the snow on the cherry, are a fleeting moment that passes quickly. The snow on the cherry symbolizes the transience and temporary nature of beauty.
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