Repeat what you say to provide exposition?
Somehow, I can't help but imagine the person on the other end saying, "Hey, you aren't listening to me! You're just repeating everything I say!"
Maybe it's just me, but Bert's eyebrows seem especially bushy in this sketch. Also, I just noticed that sometimes I refer to his eyebrow(s) in the singular and sometimes in the plural. Not sure if there's any rhyme or reason to that.
Once again, Ernie tries to portray anger without really being able to change his expression. The results are a bit uneven.