（）problems you have, ask Harry here to help you. He knows everything.

单项选择题Francis Preston Blair Jr. , （） born in Kentucky, lived and practiced law in Missouri.

A. was
B. although
C. he was
D. who he was

单项选择题By the time you arrive, I （） working for two hours.

A. will be
B. can
C. will have been
D. have been