44. We must _____ good relations with our classmates because co-operation is essential to us, modern people.
It is important that he _______ placed in an appropriate job.
I would love _______ to your birthday party last night, but I had to attend an important meeting.
Since you have made such good preparations,there _______ be any problem about passing the coming exam.
My new novel has disappeared.Who _______ have taken it?
—The winner of the race is a tall and thin boy with thick glasses. —Then it _______ be my friend, Mike, who looks like a “meat ball”.