How the sentences are made
Each sentence starts as its diagram: who does what, which word each modifier hangs from, which line every word sits on. The words are then read off that plan from lists where every word is tagged (noun, verb and the kinds of things it can act on), so the key is right by construction and the grammar holds: “a” or “an”, verb forms, objects that make sense. A sentence that could be read two ways is never used.
The eleven levels
- Subjects and verbs, with articles, adjectives and possessives.
- Adverbs, on verbs and on adjectives (“very”).
- Direct objects.
- Indirect objects.
- Linking verbs: predicate nominatives and predicate adjectives.
- Prepositional phrases, as adjectives and as adverbs.
- Compound subjects and compound verbs.
- A review of levels 1 to 7.
- Appositives.
- Compound sentences.
- Adverb clauses.
An example from set ABCDEF
“Omar carefully read Rosa a funny poem.” Omar is the subject and read the verb, on the base line. Poem is the direct object, after a line that stops at the base line. Rosa is the indirect object: she is who the poem was read to, so she sits on a line under the verb, joined by an empty slant. Carefully hangs under read; a and funny hang under poem. Open set ABCDEF (sentence 2).
Questions
How do you diagram a sentence?
Draw a base line. Write the subject on the left and the verb on the right, with a short line between them that crosses the base line. Put a direct object after a line that stops at the base line, and hang adjectives and adverbs on slanted lines under the words they describe.
How do you diagram a prepositional phrase?
Hang it under the word it modifies. The preposition goes on a slanted line and its object on a short line at the foot of the slant, with the object’s own modifiers under it. A phrase that tells which one hangs under a noun; one that tells where, when or how hangs under the verb.
How do you diagram an indirect object?
Put it on a short line under the verb, joined by a slanted line with nothing written on it. The empty slant stands for the “to” or “for” you could add: “Maya baked Leo a pie” means she baked a pie for Leo.
What is the difference between a predicate nominative and a direct object?
A direct object follows an action verb and receives the action: Leo kicked the ball. A predicate nominative follows a linking verb such as is, was or became and renames the subject: Leo became the captain. In the diagram the direct object follows a straight line, the predicate nominative a line slanting back toward the subject.
How do you diagram compound subjects and verbs?
Give each subject or verb its own short line, one above the other, and join the lines to the base line with a fork. A dashed line between them carries the conjunction, such as “and” or “or”.
My textbook draws some diagrams a little differently. Which is right?
Usually both. This page follows Reed and Kellogg’s Higher Lessons in English, where the system began. Books today agree on the main lines but differ on small points, such as dotted or dashed lines and where a conjunction is written. Open “Conventions used here” to see each choice.
How do I use this with a class?
Share with class sends a link to the same sentences. Print gives a worksheet with a drawing space for each sentence, then a key with every diagram drawn. To stop copying, print a class set: each student gets different sentences, and the keys follow.
Can a key be wrong?
Each sentence is built from its diagram, so the key matches it by design. The words come from tagged lists, so articles, verb forms and objects fit. Each sentence also has only one reading: no phrase could belong to two different words.
Diagram conventions from Alonzo Reed and Brainerd Kellogg, Higher Lessons in English (revised edition 1896, Project Gutenberg), lessons 4 to 76, with Kitty Burns Florey’s “A Picture of Language” (American Educator, 2008). Checked 26 October 2026.