“You are my friend!” said Sally.

These ones are perfect! Inside the quotation marks you can write something that somebody said, exactly as it was said!

And the exclamation or question mark shows the feeling, the volume etc. so it’s ok to have it in the quotation marks.

“Are you my friend,” asked John.

“You are my friend,” said Sally.

These ones are ok too, provided they are followed by the rest of the sentence, example:

“Are you my friend,” asked John,”or will you betray me?”

“You are my friend,” said Sally,”now I am sure!!”

It could also be “You are my friend.” said Sally.

With the full stop, it just shows that Sally didn’t emphasize.

As for a rule, well – there are so many different ways quotations can be used, so it’s hard to tell you exactly what you do in each case. But periods and commas ALWAYS go inside of the quotation marks (example- “You are my friend,” said Sally, “and I’m glad.”)

“Are you my friend,” asked John. (No it is not acceptable) You can’t have a (comma) just opened like that, you have to close the sentence because it just leaves you wondering what he’s going to say next.

“You are my friend!” said Sally. (Yes it is acceptable)

You don’t really have to add anything after that so that expression can stand strong on it’s own.

“You are my friend,” said Sally. (Again, not acceptable)

You can’t leave a comma just hanging like that. Commas mean you have something else that’s going to be said.

Hopefully this is some help to you.

i found this website that looked okay:

http://grammar.uoregon.edu/punctuation/quotations.html