Difference of intonation
"He didn't come to the party because he was busy. " This sentence has two meanings. The first one is as follows ." He didn't come the party, because he was busy ". "The second one is as follows. He didn't come the party. Because he has another reason not because he was busy.
Above two meanings is different meaning and nuance.
My question : What is the difference in intonation between these two? And why? Please tell me.