Kelly was telling Elliot some jokes.
Example: "Why did the man throw a clock out the window?"
"He wanted to see time fly."
Elliot thought the jokes were funny. Or at least, he knew he was supposed to think they were funny (it's hard to imagine he understood any of the puns).
So he made up his own.
"Why did the tiger come and get me?"
"To take me to France!"
Nobody got it, but Elliot tittered to himself for a bit.