The main thing for me is the ratio of lessons to students. Then you can read their profile and watch their video. You can also look at their non-teacher profile to see if their corrections, answers, and comments in this community are useful and if they know how to speak standard English (sadly, some native speakers don't). The “find a teacher” (搜索教师) page lets you filter for professional teacher versus community tutor, languages taught, additional languages spoken, price, and other criteria. You can even enter your own custom search terms (for example “phonology”) in the field. That’s how I choose my Chinese teachers, and that’s how my students choose me.

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