Differentiate Jokes

Why do people say tunafish, rather than just tuna?

Is that to differentiate from the tunacow and tunagiraffe

Couple's Daily Question Mug

Couple's Daily Question Mug

Why do differentiating mathematicians prefer Manhattans to Mojitos?

Ryes over rum.

What do you call an invalidation of someone's argument because they cannot differentiate between their and they're?

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