I'll pay that
This is when you say you'll pay, but you're lying. You're like a kid who promises to clean their room, but it's still a pigsty by Monday.
"I'll pay that," he said, even though he had a $5 bill and a dream.
She said, "I'll pay that," and then she went to sleep and forgot about it.
He said, "I'll pay that," and then he spent the money on a pizza.