Sentence World is a world in Mario's Early Years! Fun with Letters. It is one of the seven islands in the game.
The world takes place around various locations, such as a garden, a kitchen, and a desert. In the garden, Luigi is sitting in the mud by a log. Mario and Princess Peach are seen posing in the kitchen. The desert is at night, and the only scenery is two cacti.
The player is a given a sentence with a blank. There are three word choices represented visually, and the player must click on the word represented by the picture that goes along with the context of the sentence. When the correct answer is given a random character or creature pops out of the scenery praising the player.