One a Day

You're supposed to laugh at least once a day.  A health thing, I suppose,  I remember reading somewhere that crying is laundering the soul, laughing is dry cleaning it.

 Are you also supposed to learn something each day?  'Cause I just did: 

The plural of octopus isn't octopi.  (Oh, the times I have erred.)  The reason is because the word octopus is Greek, and the plural i is Latin.  And the two aren't supposed to mix, I guess?  Anyway, the correct plural is apparently octopodes. Fact learned.

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