реши

Краткий ответ:

1. A: When did you start learning French?
   B: Two years ago while I was preparing for my A levels.

2. A: I didn’t know you had a dog.
   B: I found her on the street a month ago while I was walking back from school.

3. A: Julie passed all her exams.
   B: Yes, I know. She told me the good news while we were having lunch.

4. A: Did you clean the attic?
   B: Yes, and I came across my yearbook!

Как выбрать время

• Past Simple — законченное действие в прошлом:
  started, found, passed, told, came.
• Past Continuous — действие, которое длилось в определённый момент:
  was/were + глагол-ing: was preparing, was walking, were having.
• Вопрос в Past Simple: Did + подлежащее + начальная форма глагола?
  Did you clean...?
• Отрицание: didn’t + начальная форма:
  didn’t know, а не didn’t knew.

Проверка: в предложениях с while длительное действие стоит в Past Continuous, а короткое завершённое действие — в Past Simple.