WORDS, WORDS, WORDS
A common example of this are the words FUN and FUNNY. You refer to an activity or situation as FUN if you think it is pleasant or enjoyable and it causes you to feel happy. However, FUNNY is someone or something that is amusing and likely to make you laugh or smile. FUNNY can also be used as a slang expression and then the meaning changes to strange, surprising or puzzling. (Collins Colbuild Dictionary)
We usually describe a party or an event as being FUN, meaning it is enjoyable. A party is not commonly described as FUNNY, as this would imply that something happened to make you laugh. It would be more usual to describe a person such a comedian or a movie as being FUNNY.
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