句型转换。根据要求完成下列句子，一空一词。（每空1分，共10分）
Your key is on the floor. （对划线部分提问）
___________ ___________ your key?
Tom is a good student. (变一般疑问句)
_________ _________ a good student?
Those are orange chairs. (变为单数形式)
_______ is        orange chair.
The baseballs are on the desk. (变为否定句)
The baseballs __________ on the desk.
This is my dictionary. (变为复数形式)
______ are ______          .