"What do you have to do?"

Translation: आपको क्या करना है ?

[Twinkle_M]

Why doesnt it accept तुमको?

[vinay92]

तुमको is equivalent to तुम्हें but since the latter is the more widely used form, perhaps Duo accepts only that. Regardless, you can report.

[Elliott728894]

is it करना and not करने because the verb "have" has to be considered as transitive ?

[vinay92]

This is not a literal translation and Hindi does not have an equivalent of the verb 'have'.

You can think of the '[Noun+को/dative-case pronoun] [verb-infinitive] [होना] ' construction as being idiomatic and meaning '[Noun/pronoun] has to [verb]' or '[Noun/pronoun] wants to [verb]'

[Elliott728894]

ok thanks

[AvanBharadwaj]

Why is "aapko karna kya hai?" wrong? I heard people using it many times.

[vinay92]

It is used only in colloquial Hindi.

While formal/standard Hindi is mostly set on word-order, in colloquial spoken Hindi, you can play around with the word order to communicate various subtleties in meaning. This is also usually accompanied by a suitable inflexion of speech (in the absence of which the sentence with nonstandard word-order may sound unnatural). Because these unfamiliar subtleties in meaning can be a source of confusion for new learners, Duolingo does not consider colloquialisms as correct and insists on formal/standard Hindi.

In the case of आपको करना क्या है?, the changed word order can be used to express exasperation, usually by placing stress on करना while speaking.