Question

They sing songs on Saturday-общий вопрос
Do they...
Альтернативный вопрос
Do they
Специальный вопрос
When
What

Answer 1

Do they sing songs on Saturday? общий вопрос
Альтернативный вопрос Do they sing songs on Saturday or on Sunday?
Специальный вопрос When do they sing songs? What do they sing on Saturday?

Answer 2

They sing songs on Saturday
общий Do they sing songs on Saturday?
альтернативный Do they sing songs or play basketball on Saturday?
специальный What do they do on Saturday?
разделительный They sing songs on Saturday, don't they?
вопрос к подлежащему Who sings songs on Saturday?