"He either had to take a taxi or walk."
In this sentence 'either had' was marked as wrong by my teacher. Can someone tell me why? Is it the word order?
You don't need 'either' in your sentence. I would remove it. He had to take a taxi or walk.
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You don't need 'either' in your sentence. I would remove it.
He had to take a taxi or walk.
If you do want it, the technically correct way to do it is thus:
He had either to take a taxi or walk.
Many speakers also accept, or even prefer, the following:
He had to either take a taxi or walk.
CJ
I disagree with your teacher's grading. The given sentence is completely acceptable grammatically.