How do you diagram a sentence using Reed-Kellogg method?

Begin with a horizontal base line. Write the subject on the left side and the predicate on the right, divided by a vertical line that cuts through the base. Place a direct object after the verb, separated by a short vertical line that stops at the base rather than crossing below it. Adjectives and adverbs go on diagonal lines slanting beneath the words they modify. For prepositional phrases, draw a diagonal line for the preposition and attach a horizontal line below it for the object of the preposition.

What are the parts of speech shown in a sentence diagram?

A complete sentence diagram shows all the major grammatical roles in a sentence: subjects (nouns and pronouns), predicates (verbs), direct and indirect objects, predicate nominatives and predicate adjectives, adjective and adverb modifiers, prepositional phrases with their objects, conjunctions joining compound elements, relative pronouns introducing dependent clauses, and subordinating conjunctions linking subordinate clauses to the main clause. Each element occupies a specific position and uses a distinct line type so its function is clear at a glance.

Can this tool diagram complex and compound sentences?

Yes. Figviz handles simple, compound, complex, and compound-complex sentences. Compound sentences appear as parallel base lines bridged by conjunction connectors. Complex sentences display dependent clauses on separate levels linked by dotted lines. The tool accurately parses multiple clauses, stacked phrases, and advanced grammatical structures so even lengthy, intricate sentences produce readable diagrams.

How can sentence diagrams help improve grammar skills?

Diagrams turn grammar into something you can see rather than just recite. Students observe directly how subjects govern verbs, how modifiers attach to specific words, and how clauses connect to each other. That visual clarity makes it easier to catch run-on sentences, spot misplaced modifiers, and fix subject-verb agreement errors before they appear in writing. Educators consistently find that sustained diagramming practice leads to stronger composition skills, improved reading comprehension, and greater confidence applying grammar rules.

Are sentence diagrams still used in schools today?

Yes. Sentence diagramming remains a cornerstone of many grammar programs, particularly in classical education, homeschool curricula, and English Language Arts courses at multiple grade levels. Many state standards include grammar analysis, and the Reed-Kellogg method is one of the most reliable frameworks for teaching it. AI-powered tools like Figviz have lowered the barrier to entry, letting teachers assign diagramming exercises without requiring students to draw every line by hand, so more class time can be spent on analysis and discussion.

For Teachers

Sentence Diagram Generator Sentence Diagrams

Paste any English sentence and Figviz AI will draw a Reed-Kellogg diagram mapping subjects, predicates, modifiers, and clauses. Ideal for grammar lessons, homework support, and language study.

✓Reed-Kellogg Diagrams✓Grammar Visualization✓Parts of Speech Labels✓Printable Worksheets

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

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

Benefits of Sentence Diagramming for Grammar Learning

Sentence diagramming gives learners a tactile, visual path into grammar that works across age groups and skill levels. Placing each word in its proper position on the diagram reinforces how subjects govern verbs, how modifiers attach to the words they qualify, and how clauses nest inside larger structures. Research in language education links regular diagramming practice to measurable gains in reading comprehension, writing clarity, and grammatical accuracy. The method is especially valuable for visual learners who find abstract grammar rules difficult to internalize. Classroom teachers also use diagrams as a diagnostic tool to pinpoint specific weaknesses in student writing and to guide instruction on sentence variety.

Sentence Diagramming in Modern Education

After a decline in some curricula during the late twentieth century, sentence diagramming has made a clear comeback in both traditional and progressive educational contexts. Classical education programs and homeschool communities remain strong advocates of the Reed-Kellogg approach, while university linguistics departments layer tree diagrams alongside the classic format to teach formal syntax. Digital tools have accelerated this revival by removing the time burden of drawing diagrams by hand, making it practical to diagram multiple sentences within a single lesson. Figviz combines established grammar pedagogy with current AI technology so that any student, teacher, or language enthusiast can produce an accurate, well-formatted sentence diagram from any English sentence in moments.

Frequently asked questions

A sentence diagram generator automatically builds a visual map of any English sentence, revealing how each word functions grammatically. Figviz uses AI to produce Reed-Kellogg style diagrams that display subjects, predicates, objects, modifiers, phrases, and clauses in a structured layout. Type or paste a sentence and the tool delivers a clear, printable diagram within seconds.

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