For Teachers

Sentence Diagram Generator Sentence Diagrams

Paste an English sentence and use FigViz to draft a Reed-Kellogg-style layout for subjects, predicates, modifiers, phrases, and clauses. Review the result before teaching or submitting it.

✓Reed-Kellogg Diagrams✓Grammar Visualization✓Parts of Speech Labels✓Printable WorksheetsLast updated: 2026-08-28

Sentence Diagram Examples

Explore diagrams for different sentence types or generate your own above

Simple Sentence Diagram

A Reed-Kellogg breakdown of a classic simple sentence, showing adjective modifiers and a prepositional phrase on diagonal branches.

simple-sentencereed-kelloggadjectives

Compound Sentence Diagram

Two parallel base lines represent independent clauses, bridged by a stepped conjunction connector for the word "and".

compound-sentenceconjunctionclauses

Complex Sentence Diagram

A subordinate clause hangs from the main clause via a dotted connector, illustrating how dependent clauses attach in a complex sentence.

complex-sentencesubordinate-clauseadverb

Prepositional Phrases Diagram

Multiple prepositional phrases cascade beneath the base line, with prepositions on diagonal branches and objects on short horizontal lines below.

prepositional-phraseparts-of-speechmodifiers

Passive Voice Diagram

The passive construction is diagrammed with the receiver of the action as subject and a "by" agent phrase branching from the predicate.

passive-voicehelping-verbagent-phrase

Relative Clause Diagram

A relative clause modifying a noun in the main clause is displayed on its own line, anchored by a dotted arc to the modified noun.

relative-clausecomplex-sentenceacademic

Prompt templates you can copy

Start with one of these examples, then adapt the subject, labels, data, or layout for your own use.

Simple Sentence Diagram

A Reed-Kellogg breakdown of a classic simple sentence, showing adjective modifiers and a prepositional phrase on diagonal branches.

Create a Reed-Kellogg sentence diagram for the sentence "The quick brown fox jumps over the lazy dog", showing horizontal base line with subject "fox" and predicate "jumps" separated by vertical line, adjectives "the" "quick" "brown" on diagonal lines below subject, prepositional phrase "over the lazy dog" branching below predicate, clean grammar education style, white background

Compound Sentence Diagram

Two parallel base lines represent independent clauses, bridged by a stepped conjunction connector for the word "and".

Create a Reed-Kellogg sentence diagram for the compound sentence "She studied hard and she passed the exam", two parallel base lines connected by a stepped conjunction line for "and", each clause with subject-verb-object properly diagrammed, clear educational grammar style, white background

Complex Sentence Diagram

A subordinate clause hangs from the main clause via a dotted connector, illustrating how dependent clauses attach in a complex sentence.

Create a Reed-Kellogg sentence diagram for the complex sentence "Although it rained heavily, the students played outside", showing main clause on top base line, subordinate clause on lower dotted line connected by "Although", adverb "heavily" on diagonal, prepositional phrase "outside", grammar textbook style, white background

Prepositional Phrases Diagram

Multiple prepositional phrases cascade beneath the base line, with prepositions on diagonal branches and objects on short horizontal lines below.

Create a Reed-Kellogg sentence diagram for "The book on the table belongs to my friend from college", showing multiple prepositional phrases branching diagonally below the base line, prepositions on diagonal lines with objects on horizontal lines, clearly labeled parts of speech, educational style, white background

Editorial evidence

How this page was reviewed

FigViz reviewed the grammar guidance against the original Reed-Kellogg text and current Purdue OWL material on sentence types and clauses. No individual grammarian or teacher endorsement is claimed. Reviewed 2026-08-28.

Important limitations

The generator creates an image draft; it does not run a deterministic grammar parser and may attach a modifier or clause to the wrong word.
Reed-Kellogg conventions vary by curriculum, especially for compound predicates, verbals, ellipses, and advanced clauses. Verify the result against the rules used in your course.
Generated labels and punctuation can contain image-model text errors, so inspect every word before printing or grading.

Sources used for review

Higher Lessons in English — Project Gutenberg
Sentence Types: Transcript — Purdue Online Writing Lab

What is a Sentence Diagram?

A sentence diagram is a graphic map of grammatical relationships within a sentence. Words are arranged on a network of horizontal and diagonal lines so that each word's role in the sentence is immediately visible. The most widely taught format is the Reed-Kellogg diagram, which places the core subject and verb on a horizontal base line separated by a vertical bar, while adjectives, adverbs, and phrases branch off on slanted lines below the words they modify. Seeing grammar laid out this way turns abstract rules into a concrete picture, helping students and language learners understand how every word connects to the rest of the sentence.

History of Reed-Kellogg Diagramming

The Reed-Kellogg system traces back to 1877, when Alonzo Reed and Brainerd Kellogg published "Higher Lessons in English." Their textbook introduced the iconic horizontal base line split by a vertical bar to separate the subject from the predicate, with modifying words placed on diagonal lines beneath the terms they describe and subordinate clauses shown on separate levels connected by dotted lines. This approach became the standard for grammar instruction in American schools throughout the twentieth century, and it continues to anchor grammar curricula in classical education programs, homeschool settings, and university linguistics courses around the world.

How to Diagram Different Sentence Types

Simple sentences: Place the subject and predicate on the base line separated by a vertical bar, with modifiers on diagonal lines below

Compound sentences: Draw two base lines (one for each independent clause) connected by a stepped line for the conjunction

Complex sentences: Show the main clause on the primary base line and subordinate clauses on separate lines connected by dotted lines

Compound-complex sentences: Combine the techniques for compound and complex structures on multiple levels

Passive voice: Place the subject (receiver of action) on the base line with the helping verb and past participle as the predicate

Questions: Rearrange words into declarative order before diagramming, then apply standard rules

What a Diagram Can and Cannot Show

A sentence diagram makes one grammatical interpretation visible: which word acts as the subject, what belongs to the predicate, and where modifiers or clauses attach. That can support comparison and discussion, but the picture is not proof that the analysis is correct. Ambiguous sentences may permit more than one reading, and an AI-generated image may place words or lines incorrectly. Treat the result as a draft, compare it with the sentence, and verify it against the conventions used in your class.

A Reliable Review Checklist

Read the base line first and confirm that the subject and predicate match the original sentence.

Trace every adjective, adverb, and prepositional phrase back to the word it modifies.

Check that independent and dependent clauses are separated and connected according to your chosen Reed-Kellogg convention.

Compare every generated label with the source sentence; image models can misspell or omit short words.

For graded work, ask a teacher or editor to review any ambiguous construction before using the diagram as an answer key.

Frequently asked questions

A sentence diagram generator turns a written sentence into a proposed visual layout of its grammatical parts. FigViz drafts a Reed-Kellogg-style image showing subjects, predicates, objects, modifiers, phrases, and clauses. Because the result is generated as an image rather than a deterministic parse, verify every word and attachment before using it as an answer key.

More Education & Language Tools

All tools →

Make your own sentence diagram with Figviz

Create a free account and get starter credits to generate your own. No credit card required.