Educational worksheet for classifying sentences by structure.

Let’s go through each sentence one by one and figure out what kind of structure it has.

We’re looking for three types:
- Simple Sentence: One complete thought (one subject + one verb).
- Compound Sentence: Two simple sentences joined together with a comma + conjunction (like “and”, “but”, “or”) or a semicolon.
- Complex Sentence: One main idea + one dependent clause (a part that can’t stand alone, often starting with words like “because”, “although”, “when”, “if”, etc.).

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1. The students were excited about the field trip.
→ Only one subject (“students”) and one verb (“were”). No extra clauses.
✔ Simple

2. I wanted to go to the park, but it started raining.
→ Two parts: “I wanted to go...” and “it started raining.” Joined by “but”.
✔ Compound

3. Because she studied hard, she passed the test.
→ Starts with “Because” — that’s a dependent clause. Then “she passed the test” is the main part.
✔ Complex

4. My dog barks loudly whenever someone knocks on the door.
→ “My dog barks loudly” = main part. “Whenever someone knocks...” = dependent clause (can’t stand alone).
✔ Complex

5. He likes pizza, and his sister prefers pasta.
→ Two full ideas joined by “and”.
✔ Compound

6. Although he was tired, he finished his homework.
→ “Although he was tired” = dependent clause. “He finished his homework” = main clause.
✔ Complex

7. We went to the beach, and we built a sandcastle.
→ Two complete thoughts joined by “and”.
✔ Compound

8. She sings beautifully when she performs on stage.
→ “She sings beautifully” = main. “When she performs...” = dependent.
✔ Complex

9. The cat slept on the couch all afternoon.
→ One subject, one verb. Nothing else.
✔ Simple

10. If you finish your chores, you can watch TV.
→ “If you finish your chores” = dependent. “You can watch TV” = main.
✔ Complex

11. They played soccer after school.
→ One subject (“they”), one verb (“played”). “After school” is just a time phrase, not a clause.
✔ Simple

12. I love ice cream, but my brother hates it.
→ Two full ideas joined by “but”.
✔ Compound

13. When the bell rings, everyone runs to class.
→ “When the bell rings” = dependent. “Everyone runs to class” = main.
✔ Complex

14. He ran fast, yet he still missed the bus.
→ Two complete thoughts joined by “yet” (which works like “but”).
✔ Compound

15. Since it was cold, we wore jackets.
→ “Since it was cold” = dependent. “We wore jackets” = main.
✔ Complex

16. The book was interesting, so I read it twice.
→ Two full ideas joined by “so”.
✔ Compound

17. She laughed because the joke was funny.
→ “She laughed” = main. “Because the joke was funny” = dependent.
✔ Complex

18. Birds fly south in winter.
→ One subject, one verb. Simple fact.
✔ Simple

19. After dinner, we watched a movie.
→ “After dinner” is a time phrase, not a clause. Main part: “we watched a movie.”
✔ Simple

20. You can borrow my pen if you need one.
→ “You can borrow my pen” = main. “If you need one” = dependent.
✔ Complex

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Final Answer:
1. Simple
2. Compound
3. Complex
4. Complex
5. Compound
6. Complex
7. Compound
8. Complex
9. Simple
10. Complex
11. Simple
12. Compound
13. Complex
14. Compound
15. Complex
16. Compound
17. Complex
18. Simple
19. Simple
20. Complex