Are the following sentences natural to a native ear?
1. Much of my work involves talking to people.
2. Up to what appointment do you have people already present here? ( I was at a clinic without an appointment and wanted to know if there is a chance of a cancellation. Generally, people cancel their appointments by phone. I wanted to know until which appointment, people have already showed up at the clinic)
3. Both of them did not want to have to do anything with each other.