Sentences and Basic Punctuation

What Makes a Complete Sentence?#

A sentence is a group of words that expresses a complete thought. Every sentence must have two things: a subject and a predicate (also called a verb). Without both parts, a sentence is not complete — it is just a fragment.

The Subject#

The subject tells us WHO or WHAT the sentence is about. It is usually a person, animal, place, or thing.

• The cat sat on the mat.
• My teacher reads to us every day.
• The red ball rolled down the hill.

In these sentences, "The cat," "My teacher," and "The red ball" are the subjects.

The Predicate#

The predicate tells us what the subject DOES or IS. It always contains a verb — an action word or a state of being.

• The cat sat on the mat.
• My teacher reads to us every day.
• The red ball rolled down the hill.

The underlined parts are the predicates. They tell us what the subjects are doing.

Complete Sentences vs. Fragments#

A fragment is a group of words that dös NOT express a complete thought. It is missing the subject, the predicate, or both.

• "The happy dog" — This is a fragment. We do not know what the dog did!
• "Ran to school" — This is a fragment. We do not know WHO ran!
• "The happy dog ran to school." — This is a complete sentence!

The Capital Letter Rule#

Every sentence must begin with a capital letter. This is one of the most important rules in writing. The capital letter at the beginning tells the reader that a new sentence is starting.

Checking Your Sentences#

After you write a sentence, ask yourself two questions:

1. Who or what is this sentence about? (subject)
2. What dös the subject do or what is it? (predicate)

If you can answer both questions, you have a complete sentence. If you cannot, add the missing part!