Each department has a faculty member in charge of TAs. There is also a faculty person in charge of each course that TAs are assisting with. Generally there are weekly meetings for the faculty and TAs working on a course. In some departments, such as Math , experienced teachers sit in and observe TA classes and then give the TA feedback and advice on teaching skills. Besides end of semester student evaluations, many departments also ask for feedback on individual instructors much earlier in the semester, either after the first month or at midterm.
Departments can then help their teachers to improve.
Instead be open to what that person is trying to communicate to you. Predicting the content of the message is helpful, as is trusting the speaker will say something relevant. You do become accustomed to accents and communication styles over time, particularly if you make an effort to adapt to them and to understand the content. English is a world language these days, as you can notice by listening to radio news programs, watching TV shows, or travelling around the globe and being able to get by with only English. However, English is spoken with different accents and even vocabulary in all parts of the world.