Every sitcom has a similar structure

There might be slight variations, especially in The Simpsons, but this structure is fairly rigid.

Act 1 - approx. 5 minutes

The setup is established.

By the end of Act 1, we see that trouble is coming.

Act 2 - approx. 10 minutes

The complications arise.

By the end of Act 2, we see that trouble is here.

Act 3 - approx. 7 minutes

We reach the climax.

This leads to a resolution, where everything comes full circle and ends as it started.

Total time elapsed: approx. 22 minutes

(adapted from "The Comic Toolbox" by John Vorhaus)