"So what do you want?"
Translation:אז מה אתה רוצה?
Why isn't it אז את מה אתה רוצה? Isn't an את needed? Is it because the object isn't specific?
Yes. You can say את מה את/ה רוצה but it means something like "which one of these (specific set of things) do you want?".
I guess it depends if you're looking for an answer that includes "et" or not:
אז את מה אתה רוצה? אני רוצה את המכונית הכחולה אני רוצה את החיים שלי בחזרה
אז מה אתה רוצה? אני רוצה שלום עולמי אני רוצה לדעת עברית אני רוצה אינפורמציה
Why is "אז איזו אתה רוצה" incorrect?
I came across this as a multiple choice question and thought all three answers were correct so then thought it was a trick question.
When learning the questions chapter I kept getting tripped up by "איזה" and "מה". From the notes etc. it seemed that any time a question made sense using the word "which" or "what" you needed to use "איזה" not "מה" "So which do you want?" seems to work as a question. So why is my answer incorrect?
Thanks for your help.
I think your answer is incorrect because איזה and מה are not interchangeable. איזה is which, מה is what.
It's true that "So which do you want?" does work as a question, but it's a different question from "So what do you want?" and you would use it in different contexts.