Watch Jennifer Lawrence's First Gig: An MTV 'My Super Sweet 16' Promo

During her SAG Awards acceptance speech, "Silver Linings Playbook" actress Jennifer Lawrence thanked MTV.

"I'll explain that," the 22-year-old said while on stage accepting her Best Actress award. "I earned my SAG card when I was 14, I did an MTV promo for 'My Super Sweet 16.' And I remember getting it in the mail and it being the best day in my entire life, because it officially made me a professional actor."

Watch Lawrence deliver her best "Mean Girls" impersonation below:

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