<p>When I was an undergrad back when the dinos roamed…I had a TA for physics lab who spoke almost no English…and what he did speak was not able to be understood. A group of us went directly to the department chairperson. The profs don’t assign the TAs. We put our concerns in writing…that we were unable to understand the material being presented in the labs. In our situation, it was actually dangerous. Our school added a second (English speaking) TA to the lab section. </p>
<p>I would go straight to the top. State the facts. Explain that you need to understand the material being presented and that you cannot because the instructor is difficult to understand due to lack of famililarity with the language. Be prepared to continue UP the food chain until you get a good reason why this can’t be fixed for you and your classmates.</p>