Beyond just sentences, anti-climaxes can be seen in literature and movies as well. Mostly present in comedies, anticlimaxes can also be found in badly written scripts, especially ones written for tv sitcoms.
Like anti-climaxes in sentences, anti-climaxes in literature consist of the build up of and resolution of conflict or tension and then the trivialization of that resolution.
There is a scene in "Raiders of the Lost Ark" that illustrates this well: In a Cairo bazaar, Indiana Jones is fighting a number of ferociously dangerous hired assassins. He has eliminated each one with his whip, brains and brawn and finally has to face the last and most menacing desperado who brandishes a big, gleaming sword. What is our hero to do? Indie, in the true sense of the anti-climax, simply takes out his pistol and shoots the guy dead.
Not only can scenes be anti-climactic, whole books (and movies that they are based on) can be anti-climactic as well. "The Wizard of Oz" is a good example. Poor Dorothy and her dog, Toto, are lost and she wants desperately to get back to loving her family. She meets some friends, and they go through all kinds of trials and tribulations so that a wizard can get her to return home. In the end, Dorothy learns that all she had to do all along was to click her shoes together and say three times, "There's no place like home." That's anti-climax number one. Then, when the girl and her dog finally get transported back home, Dorothy realizes that it all had been a dream. That's anti-climax number two.
The definition of anticlimax is: An abrupt shift from a serious or noble tone to a less exalted one--often for comic effect. Adjective: anticlimactic. Etymology: From the Greek, "down a ladder."
Some examples are:
1) "The holy passion of Friendship is of so sweet and steady and loyal and enduring a nature that it will last through a whole lifetime, if not asked to lend money."
2) "Not only is there no God, but try getting a plumber on weekends."
3) "And as I’m sinkin’
The last thing that I think
Is, did I pay my rent?"
(Jim O'Rourke, "Ghost Ship in a Storm")