It is a great concern that the school is now ____ for experienced teachers.

----You look tired, Jack. ----I feel quite rested, _______.

 We may find that learning a foreign language does not have to be________learning our mother tongue，but can in fact be twice ________.

A model or an experiment in a science class can help us see things which would_______ remain hidden.

–I _______ think it’s a northern university. So many restaurants serve northern food.--That’s because the students here are _______ from the north.