Asked by rfvv

1. I can swim well.
2. I could swim well.
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What is the difference between the two sentences?
Is 'could' politer than 'can' in meaning?
Answered by Steve
<u>could</u> is the past tense of <u>can</u>

I can swim well.
Yesterday I could swim well.

Then there are the conditional and perfect uses, but maybe you're not after those.
Answered by Writeacher
Steve is correct.

In addition, this webpage should have additional information you can use:
http://grammar.ccc.commnet.edu/grammar/auxiliary.htm#can