I was solving a test on modals and there was the following line:
What was the problem? Why _ leave early?
The proposed fill-in combinations were:
- had you to
- did you have to
- must you
- you had to
I picked 1 and 2, but the key to the test contained only choice 2.
I've consulted Quirk et al. and it says that in operator constructions (that is, for example, in interrogative sentences, when some auxiliary should be put in the 'operator' position at the beginning of the sentence) 'have to' may be treated either as:
- A 'main verb', which requires DO-support:
Do we have to get up early tomorrow?
- An auxiliary. Here, 'have' itself turns into an operator and participates in subject-operator inversion, so no DO is necessary. He notes that this usage is 'British English, somewhat old-fashioned':
Have we to get up early tomorrow?
Does this mean that "Why had you to leave early?" is also a passable answer?
I've found an instance of "But go on, why had you to go?" in The Good Apprentice by Iris Murdoch.
I'm curious whether any native speaker uses constructions like "Why had you to ..." in real life or is it always "Why did you have to ...".