Considerable effort has been expended to locate a native/near native-speaking tutor so that the class session can be a valuable opportunity to enter the world of the new language. Using English with the tutor, with each other, and even in whispered asides and comments, undermines the very purpose of the session.
REMEMBER: English will not be used during session with a tutor. After all, since the tutor is not a teacher, since grammatical questions are out of place, since learning is dependent on your prior multimedia work, WHY should you want to use English? You will find that not using English is easier than you think, IF YOU SIMPLY TRY!