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She works in a travel agency. is the most popular phrase on the web.

She works at a travel agency. 111,900 results on the web	She works in a travel agency. 118,800 results on the web More popular!
Some examples and use cases from the internet:	Some examples and use cases from the internet:
It is right that passengers need to be informed if they are booking a blacklisted plane somewhere, at a travel agency, for example, but it is often the case that passengers decide to take a domestic flight only when they are already in a particular place. He can't quite remember where the site is, so he stopped at a travel agency. plane ticket reservation at a travel agency in the physical presence of the customer by means of a network of computers; All right, boss, his wife works at a travel agency on K Street. I work at a travel company. I work in a travel agency. I'm one of the partners. I work for a travel agency. An escaped mental patient is holding people hostage in a travel agency.	It's a great cover, a travel agency. It wasn't a travel agency. Says he's setting up a travel agency. I'm a partner in a travel agency and... I work for a travel agency. I work in a travel agency. I'm one of the partners. All this trouble to have me infiltrate a travel agency. An escaped mental patient is holding people hostage in a travel agency.

She works at a travel agency.

111,900 results on the web

She works in a travel agency.

118,800 results on the web

More popular!

It is right that passengers need to be informed if they are booking a blacklisted plane somewhere, at a travel agency, for example, but it is often the case that passengers decide to take a domestic flight only when they are already in a particular place.
He can't quite remember where the site is, so he stopped at a travel agency.
plane ticket reservation at a travel agency in the physical presence of the customer by means of a network of computers;
All right, boss, his wife works at a travel agency on K Street.
I work at a travel company.
I work in a travel agency. I'm one of the partners.
I work for a travel agency.
An escaped mental patient is holding people hostage in a travel agency.