Yo mama's so fat, when she fell I didn't laugh, but the sidewalk cracked up.
Yo Mama So Fat
Explanation
This is a classic roast using hyperbole. It plays on the idea that the person's mother is so overweight that her fall caused significant damage, even to inanimate objects like the sidewalk.
Sofia
Your mama, so fat, she fell down on the sidewalk. I didn’t laugh, but the sidewalk broke. Period