In the course book DaF kompakt A1, I found the sentence:
Was macht Sylvie alles?
I can understand question without the word alles:
What does Sylvie do?
But the word alles confuses me.
The word »alles« means »everything«. You are asked to tell everything that Sylvie does. You are not asked what Sylvie is doing in a special situation, or at a special moment. You are asked what Sylvie does generally. In her whole live, all day long.
The word »alles« is used in similar Questions:
Was können Sie alles?
Here you are encouraged to tell all of your skills.
Wen kennst du alles?
Here the questioner wants to hear a complete list of all people you know.
To add to Hubert's excellent answer, "alles" in this context can be translated as "in all," (rather than simply "all").
So "Was macht Sylvie alles?" would translate as, "What does Sylvie do in all?
And as Hubert pointed out, the meaning would be "everything."