Question

Выберите предложение, в котором есть ошибка, и исправьте ее  
1. You know him, don't you?
2. Who knows him?
3. You know him or not?
4. Do you know him?

Answer 1

Думаю, что неправильно третье.... Должно быть Do you know him or not?

Answer 2

3. Do you know him or not?