Cover Letter

Would anybody have a sample cover letter that they used when submitting their application?

application for what exactly, which circumstances, etc? A bit more detail would help to provide more structured response, but to be honest, it's usually vastly different since folks have variety of different personal circumstances. Look up "sample cover letter for [reason]" in your favorite search engine and you should see a few templates.

May be I should have written it better.

Looking for a sample cover letter for citizenship by naturalization with more than 6 weeks of absence from the state.

Not sure about others, but I've just printed out an Excel sheet with dates (to/from), country, days gone and reason for each year + total days being absent. Haven't got an approval yet, so can't say if it worked, but that's one way of handling that.
Also, I assume you mean throughout previous years, not this one? If you're gone for 6+ weeks in the last year, you might have to wait another one.