P's

When the teacher is very strict, the students must mind their P's and Q's.

When the bartender totals the bill for a customer who is drunk and angry, he must be very careful to mind his P's and Q's.

Tom had to mind his P's and Q's when he met Mary's parents for the first time.

This sentence employs two a's, two c's, two d's, twenty-eight e's, five f's, three g's, eight h's, eleven i's, three l's, two m's, thirteen n's, nine o's, two p's, five r's, twenty-five s's, twenty-three t's, six v's, ten w's, two x's, five y's, and one z.

[Verse 1]:[…]I wash this with Persil, and I wanna make p's of rhyming still.

What kind of things that you have. When I find out don't expect me to stop. I'll come for the P's that you stack. And come for the food that you blot.