Where is the girl going?
or
Where the girl is going?
Is/subject/ -ing in present continuous questions Which one is right according to the Grammer?
Where is the girl going?
or
Where the girl is going?
Is/subject/ -ing in present continuous questions Which one is right according to the Grammer?
Word order in questions is different from word order in declarative statements.
In a simple declarative statement, we say subject-verb-object, with "helping verbs" following the "is/are". "The girl is going". (Usually we'd follow that with some object or prepositional phrase, like, "The girl is going to work.")
In questions, we say interrogative-to be-subject-helping verb. "Where is the girl going?" "Who was the policeman arresting?" etc.
There are other forms but these are the relevant ones.