1. I _______ swim when I was five years old.
2. You _______ smoke here - it's forbidden!
3. She _______ be at home - her car is in the driveway.
4. You _______ come to the meeting if you're busy.
5. _______ I use your phone, please?
6. You _______ see a doctor - you look terrible!
7. It _______ rain tomorrow - I'm not sure.
8. I _______ to buy milk - we have none left.
9. Which sentence is CORRECT?
10. You _______ studied harder for the exam. (past regret)
11. I _______ help you tomorrow.
12. _______ you help me with this problem? (polite request)
13. He _______ be at home - his lights are off and car is gone.
14. Students _______ wear uniforms at this school. (external rule)
15. She _______ missed the train - she's not here yet.
16. You _______ bring anything to the party. (not necessary)
17. If I had known, I _______ helped you.
18. _______ we go to the cinema tonight? (suggestion)
19. When I was young, I _______ play in the park every day. (past habit)
20. Which sentence is INCORRECT?
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