Identifying Subjects and Predicates

Being able to recognize parts of a sentence, such as subjects and verbs, is essential to avoid agreement errors and sentence structure errors.
A sentence can be divided into two parts: the subject and the predicate.
The subject identifies the topic of the sentence.  It tells us what the sentence is about.
The predicate makes a statement about the subject.
While the predicate may also include other words such as objects and prepositional phrases, the predicate will also contain the main verb.
It is easier to look for the verb first, since every sentence must contain a verb.
The verb can be an action word or a linking verb such as "are/is, etc., seems, feels, appears..."
Once the verb has been identified, you can ask the question who? or what ? after the verb. The answer will identify the subject.
Look at the example below.  Once you identify the verb "run,"  ask the question" Who runs?"
The answer "Judy and her dog" will be the sentence's subject.
Other parts of the sentence "on the beach every morning" are a prepositional phrases and an adverb, which cannot be subjects.

Judy and her dog 
run on the beach every morning.

 Some sentences have more than one subject.
In the example above, both "Judy and her dog" are subjects.
That is called a compound subject because two or more subjects are connected with a coordinating conjunction , such as "and."
However there is only one verb: "run."

Some sentences have more than one verb that refers to the same subject.
In the example above, both "walked" and "admired" are verbs that refer to the subject, "Judy."
Those are called compound verbs.

walked slowly through the art gallery and admired the powerful sculptures exhibited there. 

Other points to remember:
The words "there" and "here" are never subjects.  In many cases when a sentence begins with "there" the subject will follow the verb.

There were three stray kittens cowering under our porch steps. 

Phrases (groups of words without subject or verb) can be found between the subject and the verb, but are never the sentence's subject.

The new library  with its many books fills  a long-felt need.

The subject  may be understood if the verb is giving a command.
In the example below, the carrots do not eat. It is understood that you should eat the carrots.

Eat those carrots!

A relative pronoun, such as who, which, what, that, can be the subject.
In that case there will probably be two sets of subjects and predicates.

SUBJECT PREDICATE SUBJECT (relative pronoun which replaces John) PREDICATE
John  is the man who  can do the job.

In the following sentence one idea is embedded  in the middle of another.

SUBJECT SUBJECT (relative pronoun which replaces  "the man") PREDICATE PREDICATE (for the first subject: the man)
The man who  came in late is the school principal.

To recognize the verb remember these points:

The verb may be more than  one word:
She will meet me at three o'clock.

The verb does not have to state action.  It could be a linking verb that points out a condition or state of being, such as "is/are, seems, appears,..."

Some verb forms do not function as verb, but can be used as nouns or modifiers.
They are called verbals.
There are three forms of verbals:

1. the infinitive: to + the verb
To fight against those odds would be ridiculous.
"To fight" is used as a noun that refers to the act of fighting.  It is also the subject of this sentence.

To fight against those odds would be ridiculous.

2. the gerund: verb with an -ing ending
Being the boss made Jeff feel uneasy
"Being" refers to the condition of being.  It is used as a noun and as a subject.

Being the boss made Jeff feel uneasy.

3. the participle: present participles also end in -ing
and past participle, which ends in -ed or can be  irregular for some vetbs, such as "eaten," "seen," "broken,"...
Jeff repaired the broken window.
"Broken" is used as a modifier which describes the window.

Jeff repaired the broken window.

The crying baby had a wet diaper.
"Crying" is used as a modifier which describes the baby.

The crying baby had a wet diaper.

If you want to read more information about verbals, go to

It is important to recognize verbals because they cannot be used as a sentence's main verb.
Using a verbal as a main verb will generate a fragment.
However, a verbal can become a main verb when it is used with a helping verb.

Being late for the interview  was a big mistake.

"Being late for the interview" is not a complete sentence,
but in the following example the helping verb "is" completes the verb form.  Therefore it is not a verbal anymore.

Mary is being late for the interview.

In closing,
understanding the function of the main sentence parts will be necessary to avoid fragments, comma splices, run-ons, and agreement errors.
And remember... each sentence is different.
The combinations are infinite, but the patterns and the sentence structures are limited.
In any sentence, a statement is made about the subject and additional words can be added to describe, modify, and add detail.

I hope this information will help you.  Let me know if you have any questions or comments about this topic.