English Grammar for Lawyers: Digital Textbook
Write Clear, Correct Legal English
Legal grammar matters because small words change obligations. In a contract, the choice between that and which, or the placement of only, can change who must do what.
This page gives you the core rules from the book for free. The full textbook at the bottom of this page adds more detailed explanations with exercises, worked rewrites and answer keys.
By Marc Roche and IDM Law, training lawyers in legal English since 2013.
Table of Contents
What You'll Learn in the English Grammar for Lawyers Book
Legal grammar isn't just about being "correct"
Shall vs must vs may
Use must for obligations, may for permission and must not for prohibitions. Shall is traditional, but it can be read as an obligation, a permission or a prediction, and courts have sometimes treated it as merely directory. Many jurisdictions still use shall by convention, so follow house style and apply it consistently.
That vs which
That introduces information that is essential to identify the noun. Which adds extra information, set off by commas.
"The Supplier shall replace any goods that are defective."
Only the defective goods are replaced.
"The Supplier shall replace the goods, which are defective."
All the goods are defective.
Note for non-US readers: British usage often uses which for both.
In contracts, the comma test is safer.
Where "only" goes
"The Tenant shall only pay rent by bank transfer."
This is ambiguous. Does it forbid other methods, or other obligations?
"The Tenant shall pay rent only by bank transfer."
Only the payment method is restricted.
Put limiting words (only, even, just, almost) directly before the word they limit.
Nominalizations
Turn noun-heavy phrases back into verbs:
"make payment of the Price" becomes "pay the Price"; "give consideration to" becomes "consider".
Subject-verb agreement
The verb agrees with the subject, not the nearest noun:
"This Agreement, together with its schedules, constitutes the entire agreement."
Split infinitives and final prepositions
Neither is an error in modern legal drafting. Fix them only when the alternative is clearer.
"The party the claim is made against" is fine; "the party against whom the claim is made" is more formal, not more correct.
11 Core Topics for Effective Legal Grammar
The workbook takes you through:
Legal Grammar Basics — What Is at Stake
Split Infinitives in Legal English
Subject-Verb Agreement
Noun-Heavy Legal Writing and Nominalizations
Ending Sentences With Prepositions
Legal Punctuation That Protects Meaning
"That" and "Which"
"Shall" and "May"
Small Words That Control Legal Meaning
Modifiers and How to Avoid Misleading
The Oakhurst Comma Case
Each topic is treated in a legal context rather than as abstract grammar theory.
Learn Through Legal Examples
This isn't a workbook full of disconnected sentences about cats, restaurants and holidays.
The examples are built around the kinds of language lawyers actually encounter.
You'll work with contracts, clauses, legal correspondence, court-related language and professional communication.
For example, the book looks at how a seemingly small structural change can affect the meaning of a contractual sentence — and then asks you to identify and fix the problem yourself.
Because recognising a problem is useful.
Being able to fix it is better.
Don't Just Read the Rules. Practise Them.
The workbook includes targeted exercises throughout the course.
You'll be asked to:
identify grammatical problems
compare alternative constructions
rewrite unclear sentences
choose between competing forms
explain why a particular construction works
apply the rule to legal drafting problems
And the answers are included, so you can check your reasoning as you go.
This makes the book useful both as a structured course and as a reference you can return to when a particular drafting problem comes up.
One Comma. Millions in Liability.
One of the most memorable sections examines the Oakhurst comma case, in which ambiguity surrounding a list in Maine's overtime legislation became central to a major dispute.
The important lesson isn't that one comma magically "won" a case.
It's that ambiguity creates room for interpretation.
The workbook uses the case to show how legal writers can restructure language so that the intended scope is clear rather than leaving the reader to fill in the gaps.
That is the underlying principle of the entire book:
If a sentence can reasonably be read in two ways, rewrite it.
Who Is This For?
Lawyers
For practising lawyers who write contracts, correspondence, memoranda and other professional documents in English.
Law Students
For students who want to develop stronger legal writing habits before entering professional practice.
Legal Professionals
For paralegals and other professionals who regularly read or produce legal documents in English.
Lawyers Working in English as a Second Language
The workbook is particularly useful if English is not your first language and you want to develop greater control over the structures used in professional legal writing.
The book is designed for both first- and second-language English speakers.
A Practical Legal English Reference
You don't need to read this book from cover to cover every time you have a question.
Use it as a working reference.
Wondering whether a sentence is too noun-heavy?
Check the nominalization chapter.
Not sure whether a clause should use that or which?
Check the scope chapter.
Unsure whether a sentence-ending preposition is really a problem?
Check the practical rule.
Writing a clause involving an obligation or permission?
Review shall and may.
Trying to work out why a sentence could be interpreted in two different ways?
Look at the modifier and punctuation sections.
The aim is simple: help you make better drafting decisions.
Should Lawyers Use "Shall" or "Must"?
Use must for obligations, may for permission, and must not for prohibitions. Shall is the traditional choice in contracts, but it is ambiguous: it can signal an obligation, a permission, or a prediction, and courts have sometimes read it as merely directory rather than mandatory. Many jurisdictions and firms still use shall by convention, so follow your house style and apply it consistently throughout a document. If you have the choice, must is clearer.
Is it Wrong to Split an Infinitive in a Contract?
No. The rule against splitting infinitives (placing a word between to and the verb, as in "to promptly notify") comes from Latin grammar, not from English usage, and modern legal drafting guides do not treat it as an error. Split the infinitive when moving the adverb would make the sentence awkward or change its meaning. Avoid it only when a different placement is equally clear and reads more naturally.
Does the Oxford Comma Matter in Legal Writing?
Yes, whenever a list can be misread. The Oxford (serial) comma is the comma before and or or in a list of three or more items. In O'Connor v. Oakhurst Dairy (1st Cir. 2017), a Maine overtime statute exempted workers engaged in "packing for shipment or distribution of" certain goods. Without a comma before or, the court had to decide whether "distribution" was a separate exempt activity or part of a single phrase, and it ruled for the delivery drivers. The case reportedly settled for $5 million.
The lesson is not that one comma decided the case. The lesson is that ambiguity invites litigation. In a contract, don't rely on a comma alone: restructure the list, using bullets or numbered subparagraphs, so only one reading is possible.
Is this Book Suitable for Non-Native English Speakers?
Yes. It is written for both first- and second-language speakers, and several features help if English is not your first language:
It focuses on structures that cause real problems in legal writing, such as that vs. which, misplaced modifiers, and noun-heavy sentences, rather than general grammar you already know.
It explains why a rule matters. Some distinctions, such as that vs. which, don't exist in many other languages (Spanish uses que for both), so learners often can't rely on instinct.
Every example comes from legal contexts, such as contracts, clauses, and correspondence, so you learn the language you will actually draft in.
The exercises include answer keys. You can check your reasoning on your own, without a teacher.
It separates traditional rules from modern practice, so you know which "rules" you can safely ignore.
