سلام بچه ها ممنون میشم حل کنید

1. was studying 2. started 3. was cooking 4. learned 5. rang 6. were laughing 7. was working 8. was doing 9. were waiting 10. was listening 11. were watching 12. arrived 13. happened 14. were walking 15. was reading 16. called 17. were preparing 18. was running 19. were having 20. entered بنظرم اولی باید wasو ingبگیره چون ساعت 9 شب کاری داشت انجام میداده اونی ک نوشتی اشتباه بود دومیم ک جواب داده بودی معلوم نبود چی نوشتی ولی انگاری ingدادی بهش ک بازم اشتباه درمیاد جوابت ما کاریو ک قبلا انجام داده بودیمو میومدیم ingمیذاشتیم نه وقتایی ک ناگهانی یا کوتاه اینجا باید ساده بیارم بدون ing