Grammar worksheet focusing on using "because" and "so" correctly in sentences.

Let's solve this grammar worksheet step by step. The task is to complete each sentence using "because" or "so", remembering to use a comma before "so" when appropriate.

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🔹 Key Rules:

- "Because" introduces the reason (cause).
- "So" introduces the result (effect).
- Use a comma before "so" when it starts the result clause.
- "Because" does not need a comma.

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Now, let’s go through each sentence:

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1. My cat was hungry _____ it ate a fish.
→ The cat ate the fish because it was hungry.
✔ Answer: so
> *The cat was hungry, so it ate a fish.*
> ("So" shows the result of being hungry.)

2. I'm tired _____ I didn't sleep well last night.
→ Tiredness is the result of not sleeping well.
✔ Answer: because
> *I'm tired because I didn't sleep well last night.*

3. Stewart bought lunch _____ he was hungry.
→ He bought lunch because he was hungry.
✔ Answer: because

4. Mary was sick last week _____ she saw a doctor.
→ She saw a doctor because she was sick.
✔ Answer: because

5. I was late for work this morning _____ I overslept.
→ Being late is the result of oversleeping.
✔ Answer: because
> *I was late... because I overslept.*

6. Sweden is a cold country _____ people wear warm clothes in winter.
→ People wear warm clothes because it's cold.
✔ Answer: so
> *Sweden is a cold country, so people wear warm clothes in winter.*

7. He didn't study _____ he failed the history exam.
→ Failing the exam is the result of not studying.
✔ Answer: so
> *He didn't study, so he failed the history exam.*

8. They weren't busy _____ they helped me.
→ They helped me because they weren’t busy.
✔ Answer: because

9. I wasn't careful _____ I fell off my bicycle.
→ Falling off the bike is the result of not being careful.
✔ Answer: so
> *I wasn't careful, so I fell off my bicycle.*

10. Catherine didn't spend much money _____ everything was on sale.
→ She didn’t spend much money because things were on sale.
✔ Answer: because

11. The room is still messy _____ I didn't clean it.
→ It’s messy because she didn’t clean it.
✔ Answer: because

12. I was angry _____ my neighbor had a noisy party.
→ Angry because of the party.
✔ Answer: because

13. Birds can fly _____ they can travel long distances.
→ Flying allows them to travel far → result.
✔ Answer: so
> *Birds can fly, so they can travel long distances.*

14. John has some more work to do _____ he'll be home late.
→ He’ll be late because he has work.
✔ Answer: so
> *John has more work to do, so he'll be home late.*

15. I'm afraid of bees _____ because they might sting me.
→ Fear is the reason — but wait! This is tricky.
We are told to use "because" or "so", but here the structure is:
"I'm afraid of bees [because] they might sting me."
✔ Answer: because

16. It was raining _____ I took my umbrella.
→ Took umbrella because it was raining.
✔ Answer: because

17. Thomas is sleepy _____ it's ten o'clock.
→ Sleepy because it’s 10 o’clock.
✔ Answer: because

18. I was lost _____ I asked for directions.
→ Asked for directions because I was lost.
✔ Answer: because

19. Olivia was happy _____ she had a great time at the park.
→ Happy because she had fun.
✔ Answer: because

20. Patrick can drive _____ he took driving lessons last month.
→ Can drive because he took lessons.
✔ Answer: because

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✔ Final Answers:

1. so
2. because
3. because
4. because
5. because
6. so
7. so
8. because
9. so
10. because
11. because
12. because
13. so
14. so
15. because
16. because
17. because
18. because
19. because
20. because

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📝 Summary Tips:

- Use "because" when explaining the cause.
- Use "so" when showing the effect.
- Always put a comma before "so" when it starts the second clause.

Let me know if you'd like this as a printable version or with explanations for each!