I don't think I can help you with your problem but I have a few comments as follows. I will guess that your wife's teacher's native language is not Chinese. If that is not true then disregard the remaining comments. If that is true, then it is my opinion that requiring a student to buy a translator is a "cop out" (in this instance, the easy way out for the teacher). It has been my experience along with many other teachers to have a wide mix of languages represented in our classes and at most we would recommend purchase of a soft or hard cover, inexpensive paper dictionary (English to Native Language). And with a little effort on the part of the teacher using on-line translators it should be sufficient to support students of most languages except for those with unique dialects.