1. She wasn’t knowing didn’t know ✔ that I was watching watched ✔ her while she was singing.
2. James was falling fell ✔ off the stairs yesterday while I was cooking cooked ✔ dinner.
3. When the train was arriving arrived ✔, we were chatting chatted ✔ with my friends.
4. When you first was coming came ✔ to this country, I was working worked ✔ as a cashier.
5. The first time I saw you, you were playing played ✔ the guitar and Bella was singing sang ✔ our favorite song by the beach.
6. I was calling called ✔ you as soon as I was hearing heard ✔ the news.
7. I don’t know what it said but when she was receiving received ✔ his e-mail, she was crying cried ✔ a lot.
8. While it was raining rained ✔ yesterday, we were swimming swam ✔ in the sea.
9. We were calling called ✔ the insurance company when our car was braking down broke down ✔ in the middle of the highway.
10. My dad was coming came ✔ home just when the game was ending ended ✔.Correctness = ✔