Basically what I want to say is: "Welcome back, Sensei! Thank you for being such a good teacher! I very much look forward to learning more from you this semester."
My first hurdle is that the only phrase I've come across that seems to equate with "welcome back" is (お)かえり なさい [(o)kaeri nasai], which from what I've heard is more of a response to someone's "I'm home!" than anything else, and may not be appropriate for school...?
I'm also twitching trying to figure out if it would use verb forms and conjugations that I'm used to (I'm barely up to "ii desu" as it is, since the bigger focus previously was on teaching us pronunciation, both syllabaries, a number of common kanji, very basic sentence structure, present tense verbs, lots of vocab, etc. I've only been taking it for a few months
). Yeaaah three months of not using the language has fried my brain. 
If you believe you have a translation or suggestion that would be appropriate, do please include kanji, too, if you know some appropriate ones because I LOVE learning new kanji (I do already know 先生 though, don't worry about that, although I can't seem to find any kanji for おかえり なさい...), and don't just write in romaji if you can, because I sorely need the practice reading the phonetics anyway
(like I said... three months not using it, argh. Although my hiragana seems to be coming back quite easily, it's really the katakana that my brain is all screwy on, probably because we learned the hiragana a lot earlier, is my guess, so I've had more practice at it).Also, anybody know if "ganbatte" has any particular kanji that goes with it? My resources suck for finding out this kind of thing.
My humble thanks to anyone who can help.
