Well, I think the image says it all.
ASK: Are you comparing something?
Than means “in relation to” or “compared to.”
ASK: Are you talking about time?
Then means “at a specific time” or “next.”
Than = Comparison
Then = Time
It’s all in the spelling. Than and Compare both have As in them (and no E) while Then and Time both have Es (and no A).
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