Secondly, although they are different concepts, in the university system, the three do have such a connection. The relationship between them is mainly manifested in the following aspects:
Most university lecturers and associate professors have master's degrees. Especially in recent years, when recruiting teachers in colleges and universities, one of the basic conditions is at least a master's degree or above.
Those who have the title of associate professor or above and have other conditions may apply for master tutor. In other words, only teachers with the title of associate professor or above are qualified to be tutors of graduate students.
Teachers who teach graduate students are basically associate professors or above. Of course, some professional courses are also taught by lecturers, but they are rare.