Grade: Grade 1 Subject: English Language Arts Unit: Sentence Structure & Punctuation Lesson: 1 of 6 SAT: StandardEnglishConventions ACT: English

Complete Sentences

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What is a Complete Sentence?

A complete sentence is a group of words that tells a whole thought. Every complete sentence needs two things: someone or something (the subject) and what they do (the verb).

Two Parts of a Sentence

  • Subject - WHO or WHAT the sentence is about (a person, animal, or thing)
  • Verb - What the subject DOES or IS (an action word or being word)

Complete vs. Incomplete

Complete sentence: "The cat sleeps." (Has a subject "cat" and verb "sleeps")

Incomplete: "The big fluffy cat." (No verb - what does the cat do?)

Incomplete: "Runs fast." (No subject - WHO runs fast?)

Rules for Complete Sentences

  • Must have a subject (who or what)
  • Must have a verb (action or being word)
  • Must tell a complete thought
  • Must start with a capital letter
  • Must end with a punctuation mark (. ? !)

Examples

Let's identify complete and incomplete sentences!

Example 1: "The dog barks loudly."

Subject: The dog (who/what)

Verb: barks (what the dog does)

Answer: This is a complete sentence!

Example 2: "Under the big tree."

Subject: None - who or what is under the tree?

Verb: None - no action word

Answer: This is NOT a complete sentence. It needs a subject and verb!

Fixed: "The bird sits under the big tree."

Example 3: "Emma plays soccer."

Subject: Emma (who)

Verb: plays (what Emma does)

Answer: This is a complete sentence!

Example 4: "Jumped over the fence."

Subject: None - who jumped?

Verb: jumped

Answer: This is NOT complete - missing the subject!

Fixed: "The horse jumped over the fence."

Example 5: "I am happy."

Subject: I (who)

Verb: am (being word)

Answer: This is a complete sentence! "Am" is a being verb.

Practice Problems

Is each one a complete sentence or not?

1. "My mom cooks dinner."

Show Answer

Complete! Subject: My mom. Verb: cooks.

2. "The red ball."

Show Answer

NOT complete. No verb - what does the ball do? Fix: "The red ball bounces."

3. "Birds fly south."

Show Answer

Complete! Subject: Birds. Verb: fly.

4. "Running in the park."

Show Answer

NOT complete. No subject - who is running? Fix: "Sam is running in the park."

5. "The sun shines brightly."

Show Answer

Complete! Subject: The sun. Verb: shines.

6. "My favorite toy."

Show Answer

NOT complete. No verb. Fix: "My favorite toy is a teddy bear."

7. "We eat lunch."

Show Answer

Complete! Subject: We. Verb: eat.

8. "Swam in the pool."

Show Answer

NOT complete. No subject - who swam? Fix: "The kids swam in the pool."

9. "The flowers are pretty."

Show Answer

Complete! Subject: The flowers. Verb: are.

10. "Because it was raining."

Show Answer

NOT complete. This does not tell a complete thought. Fix: "We stayed inside because it was raining."

Check Your Understanding

Answer these questions about complete sentences!

1. What two things does every complete sentence need?

Show Answer

Every complete sentence needs a subject (who or what) and a verb (action or being word).

2. What does the subject of a sentence tell us?

Show Answer

The subject tells us WHO or WHAT the sentence is about.

3. What does the verb of a sentence tell us?

Show Answer

The verb tells us what the subject DOES or what the subject IS.

4. What is wrong with "The happy puppy"?

Show Answer

It has no verb! We do not know what the puppy does. A fix: "The happy puppy plays."

Next Steps

  • Practice writing your own complete sentences
  • Check your sentences - do they have a subject AND verb?
  • When you are ready, move on to Punctuation Basics
  • Great job learning about sentences!