—The research on the new flu virus vaccine is challenging and demanding. Who do you think can do the job?     —_______ my students have a try?

 One of our rules is that every student          wear school uniform while at school.

When we were young, every evening my brother and I ______ stay at home waiting for our mother.

----Whose book is this?----It _______ our geography teacher’s. You see, his name is on it. 

Something terrible       have happened if Li Chang was not coming to eat in his restaurant as he always did.