You have to be more specific what following inventions are you talking about?
B and its easy to remember
shell be comming around the mountain when she comes
She'll be comming around the moounatin when she comes yeee ha
I would say that emphasis gives a piece importance or value. Maybe even that "special touch". With emphasis, it draws attention to whatever you are introducing or showing. It gives that object a feel of expression and intensity. <em>I hope this helps!!!</em>