The key to exercise solutions in chapter Unit 108 - Superlative for the textbook English Grammar in Use with authors Raymond Murphy from Cambridge University Press
Question
What do you say in these situations? Use a superlative + ever.
Answer
That’s the most boring movie I’ve ever seen.
That’s the funniest joke I’ve ever heard.
This is the best coffee I’ve ever tasted.
That’s the furthest / farthest I’ve ever run.
It’s the worst mistake I’ve ever made. / It was the worst mistake I’ve ever made.