Теорія:

1. We often use the past continuous with while to talk about actions happening at the same time.
Ми часто вживаємо минулий тривалий час разом з while, коли говоримо про дії, що відбувалися одночасно.
 
While + [the past continuous], [the past continuous].
[The past continuous] while + [the past continuous].
 
While we were having dinner, Nick was doing his homework.
Nick was doing his homework while we were having dinner.
 
2. We often use the past simple with when to talk about actions that happened one after another.
Ми часто вживаємо минулий неозначений час з when, коли говоримо про дії, что відбувалися одна за одною.
 
When  + [the past simple], [the past simple].
 
When we had dinner, Nick did his homework. = Fist we had dinner, then Nick did his homework.
 
3. We often use the past continuous and the past simple together to say that something happened in the middle of something else.
Ми вживаємо минулий тривалий час разом з минулим неозначеним, коли говоримо про подію, яка відбулася під час іншої.
 
While + [the past continuous], [the past simple].
[The past continuous] when + [the past simple].
 
While we were having dinner, Joe came.
It was raining when we got out.
 
4. We don't use the past continuous with some verbs. With those verbs, we use the past simple.
Ми не вживаємо минулий тривалий час с де-якими дієсловами. З ними ми вживаємо the past simple.
 
believe вірити, cost коштувати, hate ненавидіти, know знати, like подобатися, love любити, need потребувати, remember пам'ятати, see бачити, understand розуміти, want хотіти, forget забувати etc.
 
She wanted to buy a newspaper.