"Most of what is needed in relationships with other people and with God can be
summarized in three phrases:
"Please,"
"Thank You," and
"I'm Sorry."

"Please" is an acknowledgement that ultimately other people have a
choice in their dealings with us, and is an expression of our need for
their involvement.

"Thank you" is a communication that we appreciated what someone else
did. We like to be appreciated, and this is one way we can let someone
else feel good.

"I'm sorry" can be an attempt to restore at least in part the respect
we owe other people that we have taken away by what we've done or
failed to do; if truly given, it carries an implicit promise not to do
that again."
http://groups.yahoo.com/group/Buddhaviharas/message/3438?var=0&l=1
http://web.archive.org/web/20060925224242/http://www.aainsa.org/ForTodAAy/Oct/23\
PleaseThankYouImSorry.htm