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Explain when you should use since and when you should use for with present perfect.
Since is used with a specific point in time - an hour, a day, a month, a year or, for example, since 8:00, since Sunday, Since January, Since 2010, or with a time clause - since I was a child.
For is used when talking about the length of time - ex. 10 minutes, 2 days, 5 months, 10 years.