Here's a subtitle of the TV drama "Sesame Street: Bert and Ernie in a Pyramid".
https://www.youtube.com/watch?v=8yiqGtZXCmQ
0:22
Burt: Yeah, look at the knowledge here. This pyramid must be centuries and thousands, even, of years old. This is great.
Perhaps Burt wants to say "This pyramid must almost be centuries and thousands, even, of years old." But it seems to me that he says "is" instead of "must". What exactly does he say?