"I saw him once" is Past Simple: I have seen him and I do not expect to see him again. "I've seen him once" is Present Perfect: I have seen him in the past (up until now) and it is possible that I might see him again.
1 de abril de 2015
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which difference?
1 de abril de 2015
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?????
1 de abril de 2015
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¿No has encontrado las respuestas?
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