When you think about a sentence, you usually think about words — not lines. But sentence diagramming brings geometry into grammar.
If you weren't taught to diagram a sentence, this might sound a little zany. But the practice has a long — and controversial — history in U.S. schools.
And while it was once commonplace, many people today don't even know what it is...
Burns Florey and other experts trace the origin of diagramming sentences back to 1877 and two professors at Brooklyn Polytechnic Institute. In their book, Higher Lessons in English, Alonzo Reed and Brainerd Kellogg made the case that students would learn better how to structure sentences if they could see them drawn as graphic structures.
After Reed and Kellogg published their book, the practice of diagramming sentences had something of a Golden Age in American schools.
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Diagram sentences! (Works on only some computers.)