Discuss:
Would you say either of them? No!
"You can swim because it's hot."
This isn't very natural. If you are trying to say - the weather is hot so you are going to go for a swim to cool down - it would be more natural to say. "It is a very hot day so we can swim in the sea/pool." Meaning: The sea/pool would be pleasant to swim in as the weather is hot.
"You swim because it's hot."
This is more of a question. You could say: "Are you going for a swim because the weather is so hot?" or "You like swimming because the weather is so hot!"
Do these two mean the same? They dont really mean the same.
Are these both natural? No.
This is an interesting discussion. Whats the context of your statement?
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