My parents ________ in Hong Kong. They were born there and have never lived anywhere else.

----Do you know our hometown at all? ----No, this is the first time I _____ here. 

—Who do you think will get the first prize?     —Mary, of course. She ________ for the competition for months.

The calculations, had they been done by hand, ______all practical value by the time they were finished.

 I’m sorry I can’t join you.  I __________ my homework.