I have slightly edited a recent job ad placed by a Chinese School on another EFL website. See below, and please pay particular attention to the parts I've highlighted in red. They imply that it's OK to teach with an F visa in China, but is this actually the case?

****** english school is an famous english traning school in ****** province.now we have many basement school here and many foreign teachers are working in our school.As the new lesson plan,we need two english foreign teacher at once.Not Part time job,we need full time teacher.This time we do not want to employ the foreign students who are studing in ****** as the visa problem.

We can accept the F visa

,but it is better Z visa.we provide the foreign teacher 4500RMB monthly,if you have riv\ch teaching experience and easy going with the students,we can consider increase the salary for you.
Job Description:
the students are aged from 6-12 yrs old.we need the foreign teacher arrival here at once,the teacher who are in China right noe is the best.

we can accept the F visa

.pls reach us if you are available.we can accept the teacher from Non english native country.