Personally, the job as a teacher _____ be challenging, for I sometimes _____ deal with some smarter but less diligent students. 

The man ______ be my father. My father is much taller.

—Do you still go jogging every morning?—Yes, I can’t think of a _______________ way to start a day.

-----Could I have a look at your i-phone5s, dad?------Oh, dear, if you_______.

—        I know by what time you want the project to be done?—By the day after tomorrow.      you finish it on time?