Question

One swallow doesnot make a summer proverb expansion

Answer 1

A "swallow" is a bird, which makes its appearance during spring.

The expression "one swallow does not make a summer" is usually used as a sort of warning. You are telling an individual not to become too happy about something; you are advising him to err on the side of caution. You are asking the individual not to get too excited just because a couple of good things have happened; there is still a long way to go yet. One good thing does not necessarily mean a happy ending.

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