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inquiry is the most popular phrase on the web.

enquiry 110,900,000 results on the web	inquiry 1379,000,000 results on the web More popular!
Some examples and use cases from the internet:	Some examples and use cases from the internet:
Whether we like it or not, much of our language is now heavily influenced by American English spellings. British English uses both 'enquiry' and 'inquiry', but not ... enquiry. See definition in Oxford Advanced Learner's Dictionary ... all the neighbouring pubs [ mass noun ] : her mind was buzzing with possible lines of enquiry. A query is a single question; an inquiry (or enquiry) may be a single question or extensive investigation (i.e. a series of questions). query, inquiry, enquiry Police are now following hundreds of lines of enquiry involving many ... She is incapable of responding to kindness and enquiry, even very gentle flirting on the ...	Your inquiry wrapped six months ago. That almost sounds like a domestic inquiry. This inquiry today is a shambles. I don't think that's relevant to this inquiry. One that covers all matters related to my inquiry. The investigation shall be accomplished independently of any judicial inquiry. A couple weeks, till after the inquiry and see what happens. We have just received an inquiry from Kansas concerning your brother.

enquiry

110,900,000 results on the web

inquiry

1379,000,000 results on the web

More popular!

Whether we like it or not, much of our language is now heavily influenced by American English spellings. British English uses both 'enquiry' and 'inquiry', but not ...
enquiry. See definition in Oxford Advanced Learner's Dictionary ... all the neighbouring pubs [ mass noun ] : her mind was buzzing with possible lines of enquiry.
A query is a single question; an inquiry (or enquiry) may be a single question or extensive investigation (i.e. a series of questions).
query, inquiry, enquiry
Police are now following hundreds of lines of enquiry involving many ... She is incapable of responding to kindness and enquiry, even very gentle flirting on the ...

Your inquiry wrapped six months ago.
That almost sounds like a domestic inquiry.
This inquiry today is a shambles.
I don't think that's relevant to this inquiry.
One that covers all matters related to my inquiry.
The investigation shall be accomplished independently of any judicial inquiry.
A couple weeks, till after the inquiry and see what happens.
We have just received an inquiry from Kansas concerning your brother.