Hallo everybody! I need your help…
We can use different prepositions with the verb “work”. In the Market Leader Course Book (Elementary level, 2004, I’ve found the following explanation:
Use “work for” when you talk about the company or organisation where someone is employed
Use “work as” + job
Use “work in” + kind of activity
Also, use “work in” with words like bank, hotel, hospital or factory
Everything seemed to be OK, but I became puzzled while trying to do exercises…
For example, why I cannot use FOR instead of IN in the sentence:
At the moment, he is working IN a travel agency
And why I cannot use IN instead of FOR in the sentence:
Are you going to work FOR a clothing company in Edinburgh?
Thank you!
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Your course book explanation is a guideline, not a prescription.
At the moment, he is working IN/FOR a travel agency.
Are you going to work IN/FOR a clothing company in Edinburgh?
These are all OK. Another, simpler guideline: Use ‘for’ for the organization and ‘in’ for the place.
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Thank you very much, that’s just what I needed to understand
I wonder how I couldn’t guess it before, because it is really very simple 
I’ve just thought about something else. Is there any initial reason of existing these two variants when speaking about somebody’s job? Does a speaker imply anything when he says: “Helen works FOR this organisation” (for example, that Helen is not a director of this organisation)?
It does not matter whether Helen is a director or not if she is not, the owner of the company. One can work for an employer and work at/in a company.
I work at a Fire Department, I work for the City of Cityname.
