Blake Lively really likes to win! The actress faced off against show host Jimmy Fallon on The Tonight Show on Monday, June 20, in a fast-paced game of Know It All — and the results were hilarious!

Lively, who wore a skintight bright blue dress that showed off her gorgeous pregnancy bump, picked Harry Potter characters as her first category — hoping her knowledge would be better than Fallon's.

But as the former SNL star picked really obvious answers, the stunning Shallows actress yelled across the table, "Come on, do better ones!" Lively, 28, eventually outwitted Fallon with the name "Hedwig."

Next up was Spanish words — Lively was adorable as she giggled her way through the round, coming up with burrito, among others. But it was the final category — four-letter words — that really stumped the actress.

Too polite to say a swear word, she shouted out, "Shoot!" Jimmy Fallon wasn't convinced.

Watch the hilarious video above.

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