A friend of mine asked me if I can teach how to recite a part of Shema with the Iddish pronuntiation to a group of non Jewish artists that have to do a show in a very important theatre. I would be pleasing if you could please tell me, if I can teach and what I can teach to those people.

There is a prohibition against teaching Torah to gentiles except under certain circumstances and for specific reasons such as preparing someone for his conversion. Teaching a gentile correct Hebrew pronunciation would however not be included in this prohibition. There is a prohibition against saying G-d's name in vain - not as part of prayer or reading a full verse of the Torah. If you teach these actors pronunciation, have them refrain from saying G-d's name, substituting "Hashem" or mumbling a word instead.