. —Why do you look worried?

—There are so many problems______.

         A. remaining to settle    B. remained settling

C. remaining to be settled    D. remained to be settled

-- Why do you look sad?

--There are so many problems _____．

A．remaining to settle   B．remained settling

C．remaining to be settled    D．remained to be settled

--- Why do you look worried?

--- Fred left the company half an hour ago. His work ____ unfinished since.

A. left                   B. was left            C. has left                    D. has been left

—Ken, why do you look so tired? 
—I _______ myself to the climate since I came here.

---Why do you look so happy?

---My aunt has bought a new car and she will invite me to go for a _____ this weekend.

A. surf               B. ride                    C. run                  D. hike