Did two your friends enter the Medical University in 2017? Общий
Who entered the Medical University in 2017? Вопрос к подлежащему
Two my friends entered the Medical University in 2017,didn't they? Разделительный
When did two your friends enter the Medical University? Специальный к обстоятельству времени
Where did two your friends enter in 2017? Специальный к обстоятельству места
Did two your friends enter the Medical University in 2016 or in 2017 ? Альтернативный
Didn't two your friends enter the Medical University in 2017? Отрицательный вопрос
Two my friends didn't enter the Medical University in 2017.Отрицательное предложение