Past perfect tense 10 предложении

1. I had done my homework by three o'clock

2. She had read the book by Friday

3. That student hadn't completed his degree work by the end of the year

4. I had arrived in Moscow by seven o'clock

5. She had found the key when I called

6. They bought the cars which we had shown them

7. When I came to work they had already completed the meeting

8. Marina had left by the 15th of June

9. When we called for Julia, she hadn’t yet got up

10. I had thought you knew about our problem

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