No, it's not. To ask is 'vragen': Waarom vraag je dat? - Why do you ask that? To question is more doubting, if I understand your question correctly. So that would be 'twijfelen': Waarom twijfel je daaraan? - Why do you doubt/question that?
Thanks for clearing that. But now I wonder, why is it daaraan and not dat? Does the verb twijfelen only go together with daaraan? Are daaraan and dat interchangeable? Sorry for the amount of questions :)
That's okay! I'll try to answer them :)
First of all: Daaraan is an adverb, dat is a demonstrative pronoun. Secondly: 'twijfelen' only goes with daaraan (waarom twijfel je daaraan? = why do you question that?) and daarover (waarom twijfel je daarover?= why are you doubting/worrying about that?). These are the only two options.
'Waarom twijfel je aan dat?' is wrong. The only other option beside there two are 'aan hem/haar/hen', so to doubt a person.
F.e.: Waarom twijfel je aan haar/hem/hen? Why do you doubt her/him/them?
Sorry if my English grammar isn't right, I'm not sure sometimes, haha.
I'm not certain, since I'm a learner as well, but I think stellen goes together with een vraag, think of it as 'ask' in the sense of 'pose' (pose a question), while vragen is just 'ask', as in asking something.
• een vraag stellen (to pose a question)
Ze stelt een vraag
• iets vragen (to ask something)
Ze vraagt rare dingen (She asks strange things)
Hope this helps.
Why do you ask about that? = Waarom vraag je over dat?
Why do you ask that? = Waarom vraag je dat?
So, the wording is slightly different.
Because when the verb is placed before 'je/jij', you mustn't add the -t.
In my opinion the English translation is incorrect. You always "ask about sth" and not "ask something", unless you "ask a question" (you can "ask sbd", but it is a different case). Or you can also "ask for sth". "Waarom vraag je dat?" should be translated to "Why do you ask ABOUT that". That is the sense of this sentence
Hi Marcin, I'm afraid I'll have to disagree with you, since you can ask something to someone, and there's a slight difference between that and ask someone about something. You can find detailed information on the OED (but you need to subscribe) or on the following link: http://www.macmillandictionary.com/dictionary/british/ask_1
Hope this helps!