(CNN) The seniors of Marjory Stoneman Douglas High School were greeted by a surprise guest speaker at their graduation on Sunday.

"Today you're graduating from high school," said Jimmy Fallon, host of NBC's "The Tonight Show," offering students a little bit of comic relief and a hopeful message just months after they survived a high-profile school shooting.

"You should feel incredibly proud of yourselves. That doesn't mean you should rest on your laurels -- or your yannys ."

"Some of you will grow up to hear yanny, some of you will grow up to hear laurel, but the most important thing for you to know is that neither of these things will matter by the end of the summer."

"Here's what will matter: you, the class of 2018, will have graduated. And you won't be classmates anymore. You'll be adults who Facebook search each other at two in the morning for the next ten years."

JIMMY FALLON CAME TO OUR GRADUATION DAWG WTF pic.twitter.com/7Mys8t5l6H — sid 🕊💫 (@sidfischer00) June 3, 2018

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