_____has your brother studied in New York? —For two years.
A. How old B. How often C. How long
Bob promises to join in the football match ______ he has to help his parents on the farm.
A. if B. as C. unless
-- Did you find the small village yesterday?
-- Yes, without any difficulty, for it has ______ changed over years.
A. hardly B. greatly C. clearly
I couldn't get through the door because there was a big box ______.
A. by the way B. on the way C. in the way
It's nice of you to ______ so much time showing me around your school.
A. take B. spend C. cost
-- Have you ever been to Shanghai, Mary?
-- Yes. I _______ there for three days with my parents before.
A. have gone B. have been C. went