In Engpsh, you can refer to a teacher as "teacher" or "professor." You can refer to a classmate as "classmate," "fellow student," or simply "student."

For example, you might say "I have a question for my teacher" or "I'm working on a group project with my classmates."

It's important to note that in Engpsh, it is not common to refer to people using terms pke "laoshi" or "tongxue," which are used in some other languages. Instead, it is more common to use specific terms pke "teacher" or "classmate" to refer to these roles.