Simple, Straightforward, Plainspoken
Way out at the end of a tiny little town was an old overgrown garden, and in the garden was a house, and in the house lived Pippi Longstocking. She was nine years old, and she lived there all alone. (1.1)
From beginning to end, this is how the story of Pippi Longstocking is written: in plainspoken language that doesn't leave you wondering about double meanings or hidden innuendos. The sentences are simple, straightforward, and easy to understand—even when they're a bit longer, like that first sentence above.
It's pretty refreshing, especially if you've just finished reading The Scarlet Letter or Moby-Dick, and it also helps to communicate one of Lindgren's main points: life doesn't always need to be as complicated as adults tend to make it.
The simplicity of the language exposes the absurd choices made by many of the book's adult characters. At the circus for instance, when the ringmaster hisses at Pippi, "Get out of here! I don't want to see any more of you," we kind of get where he's coming from. She hasn't been following typical circus protocol, and he's understandably annoyed.
But when Pippi replies, "Why do you always have to be so unfriendly? … I just want to fight the Mighty Adolf," our allegiance shifts. She's been nothing but straightforward, and the audience loves her. The ringmaster asked for a volunteer, and she's volunteering—it's only the ringmaster who can't relax and enjoy the moment. Why? Because he wants to remain in control.
But he's making things a lot harder than they need to be—something he'd understand if he'd read Pippi Longstocking before he met her.