If I'm not mistaken, Calc follows the usual IF-THEN-ELSE, so it should be
=IF(A5<=TODAY();"到期";"未到期")
(not comma, semicolon!)
--
"I am at a rough estimate, thirty billion times more intelligent than you. Let me give you an example. Think of a number, any number."
"Er, five."
"Wrong! You see?"
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