Общий вопрос - Does Dan write a letter? Does his friends live in Dover?
Альтернативный вопрос - Is Dan writing a letter? Is his friends lives in Dover?
Вопрос к подлежащему - Who is writing a letter? Who lives in Dover?
Специальный вопрос - What does Dan write? Where do his friends live?
Разделительный вопрос - Dan is writing a letter, isn't he? His friends lives in Dover, don't they?
Общий вопрос - Does Dan write a letter? Does his friends live in Dover?
Альтернативный вопрос - Is Dan writing a letter? Is his friends lives in Dover?
Вопрос к подлежащему - Who is writing a letter? Who lives in Dover?
Специальный вопрос - What does Dan write? Where do his friends live?
Разделительный вопрос - Dan is writing a letter, isn't he? His friends lives in Dover, don't they?