______ a week do you walk your dog —Lessthan three times a week.

It suddenly ______ to me that we could use a computer to do the job.

Although the first part of the book is easy， the rest ______.

Mr.Black is a professor of chemistry,he is a famous writer.[ ]

This printer is of good quality. itbreak down within the first year. A．Should B．Would C．Could D．Might