Nani-o kootyoo-wa [Tanaka sensei-ga dare-ni dasita syukudai-ni] tnani-o tukekuwaeta-no?
what-acc principal-top Prof Tanaka-nom who-dat assigned homework-dat what-acc added-Q
*Who is the person x and what is the thing y such that the principal added y to the homework who Prof. Tanaka assigned to x?