Fundamental Rules for Writing Sentences

How to write solid sentences.

Here then are the rules for writing well-formed sentences.

Rule #1: Write using sentences

The first word of a sentence begins with a capital letter.

Sentences end with a full stop or terminator such as a period, question mark or exclamation mark.


I went to the store.
Yesterday was a good day for writing!
Why are you asking me that?

Rule #2: Write using complete sentences

To be complete, a sentence must have a subject and a verb.

The subject is the noun (person, place or thing) about which you are writing.


you me him Sarah a book

The verb is the action being performed by the subject.


walking sitting reading

These are examples of complete sentences:

Suzie ran to the store.
Suzie ran very fast.
She arrived at the store in no time.

This is an example of the use of a verb of being (am).

I am Brian.

Rule #2 Challenged!

What about this sentence?


The subject “you” is implied, as is the object clause “what you’re doing”

A more complete but less thrilling sentence might read:

You, stop what you’re doing!

Note the reference to less thrilling, which we’ll discuss later in breaking the rules.

Rule #3: Order your words correctly

The most common order for the parts of a sentence is: subject, verb and object (if present).

The object is the receiver of the action.


Brian threw the ball.
[subject] [verb] [object]

Rule #4: Parts of speech (subject, verb and object) aren't always single words

Subject, verb and object aren’t always single words.

People who write a lot get better at writing.

"People who write a lot" is a subject phrase or predicate…

People who write a lot get better at writing.

“get better" is the verb…

People who write a lot get better at writing.

“at writing" is an object clause (the receiver of the action).

Rule #5: Compound sentences are combined using Commas and a conjunction

If two things happen, use the conjunction only:

Raymond stopped what he was doing and [he] ran to the gas station.
Would you like to have a seat or [would you like to] leave?

How about compound subjects?

Sally and I went to the races.

How about compound verbs?

Sally laughed and played.
Sally and I joked and laughed at the races and later at the movies.

What about the commas?

Use commas to separate every item in a list from the other except the last, which is separated with the conjunction “and” or “or”:

Raymond stopped, looked both ways and ran to the gas station.
Would you like to have a seat, stand or leave?
Bob, Pete, Sam and Ray hiked, slept and ate in the forest and by the lake.

Rule #5B: The Oxford Comma

A comma before the conjunction is known as the Oxford comma.

The Oxford comma is encouraged in Strunk and White but discouraged in the Chicago Manual of Style, which is edging out the older manual as the current standard.

Examples of the Oxford Comma:

Raymond stopped, looked both ways, and ran to the gas station.
Would you like to have a seat, stand, or leave?

Rule #6: Subject Verb Agreement

To write a correct sentence, any verbs used in the sentence must match the subject of the sentence. Subjects and verbs must agree with one another in number. For instance, if a subject is singular, its verb must also be singular; whereas, if a subject is plural, its verb must also be plural. This is known subject verb agreement, and it's vital that you internalize this concept to become a proficient writer. Here are some examples:

The boy is young.
The boys are young
The man was old.
The men were old.
The squirrel sits in the tree.
The squirrels sit in the tree.

Again, experience and memorization will allow you to learn the rules. In the meantime, you should depend heavily on good grammar checking software.

Rules of Subject Verb Agreement

  1. Subjects and verbs must agree in number.
    The bird sits in the tree.
    The birds sit in the tree.
  2. Subordinate clauses that come between the subject and verb don't affect their agreement.
    The bird, which is bright red, sits in the tree.
  3. Prepositional phrases between the subject and verb usually do not affect agreement.
    The colors of the rainbow are beautiful.
  4. When sentences start with "there" or "here," the subject will always be placed after the verb.
    There is a fly on the wall. These are the flies you requested.

You can find the remainder of the rules in the online post 20 Rules of Subject Verb Agreement.