On the surface this does not sound right to me. The main issue will be the language in you lease agreement. Normally a lease will say who and how many people can live in the dwelling. Read your lease agreement and see if there is any 'unusual' language in it that would allow such an unorthadox arrangement. After that you will need to get advice from a real estate attorney.
Robert McGuire ASR
Your Castle Real Estate
Direct - 303-669-1246
Contracts on room rentals can vary from contract to contract. Typically the landlord can rent rooms out to anyone of their discretion, but it depends on what is written in the lease agreement. The rental form that you would have signed would have stated the terms of your rental agreement. It should have specified who is on the lease, how many people will be renting and living at the premises, and what the process of replacing tenants will be. If the lease has a sub-lease clause then you would be able select other tenants, but this process also must be approved by the landlord. Ultimately, it will depend on how the lease was written. I would recommend having an attorney review your lease. But read through it thoroughly and you should be able to identify what your rights are.
If there is anything I can do personally to help call me at 719-229-5062