01 · Frame
Introduction
Improve your grammar with sentence diagrams, not LLMs. What words mean depends partly on how they relate to other words in a sentence. Syntax describes those relationships and the roles words take in them. Seeing the structure more clearly can improve both reading and writing.
After at least 12 years of studying grammar and syntax, most of this will be familiar. This review brings back the terms for relationships you already use when you read and write.
Max Morenberg's Doing Grammar is the book I have always used to refresh my understanding of syntax. This guide follows much of his approach, with coding agents helping to turn sentence diagrams into interactive tools.
reading the diagram
Form and function answer different questions
Each diagram label tells you what a word or group of words is and what job it does here. Grammar calls those two answers form and function.
What kind of unit is it?
NP · Noun phrase
The words form a noun phrase.
What job does it do here?
Subj · subject
That noun phrase is the subject of the sentence.
| Form · what it is | Function · what it does |
|---|---|
NPNoun phrase | Subjsubject |
VPVerb phrase | Predpredicate |
In the first diagram, the horse raced past the barn has the form NP and the function subject.
the problem
The sentence is grammatical, but difficult to read
The horse raced past the barn fell.
Most readers hesitate at fell. Up to that point, raced looks like the main verb. The final word forces a second reading, but the sentence is well-formed English.
A fuller version makes the intended grouping easier to see:
The horse that was raced past the barn fell.
The horse did not race past the barn. Someone raced the horse, and the horse fell. The words raced past the barn identify which horse the sentence is about.
the stakes
A grammar dispute led to a $5 million settlement
In 2017, dairy drivers in Maine sued for unpaid overtime. State law listed work that did not earn overtime, and the drivers delivered food rather than packed it. The case turned in part on how the final words in this list were grouped:
packing for shipment or distribution of perishable food
| Grouping | What it means |
|---|---|
| packing for [shipment or distribution] | This names one kind of work: packing. Delivery is not exempt, so the drivers are owed overtime. |
| [packing for shipment] or [distribution] | This names two kinds of work. Distribution is exempt, so the drivers would receive nothing. |
The missing comma did not decide the case by itself. The court considered the grammar and the rest of the law, found the wording ambiguous, and applied Maine’s rule that such uncertainty favours the worker. The case later settled for about five million dollars.
The individual words were not in dispute. The dispute was over which words belonged together, and that difference changed what work the law covered.
Ten sentences from this lesson, one decision at a time.