Complex sentence: In transit stations, a mezzanine level is often encountered between the station's entry elevation and the platform level, where the service is boarded; this may contain the area where fares are paid, or provide access to different service platforms.
Split into simpler sentences: In transit stations, a mezzanine level is often encountered between the station's entry elevation and the platform level, where the service is boarded. This may contain the area where fares are paid, or provide access to different service platforms.