补充楼上,还有 clinician,technician,politician,等用 cian 结尾的.
还有什么 man,milkman,postman,policeman,chairman,等,和什么什么woman,比如说 policewoman...
还有一些没什么规律的,比如说 student,correspondent,president,astronaut,athlete,coach,staff,peasant,king,queen,prince,princess,pundit,prostitute,还有什么 iron smith,gold smith,系列的,等等.