___ difficult the task may be, we must fulfil it this month.
It is everyone’s duty to ______ our school a pleasant place to learn in.
Ever since my brother graduated from the university, he _______ in the present company for 15 years and he is now chief engineer of the company .
______ me the truth, or I’m not going to leave the room.
It is said that the weather will ______ hot for another three or four days.
—Who called just now, Sam?—It’s Terry. She asked _____.