—Who _____ it be that is knocking at the door?—It ______be father, but I’m not sure.
Obviously, he’s very disappointed at the way things have_____.
This lecture is by no means the most boring. I’ve attended_____.
The mother felt herself____ cold and her hands trembled as she read the letter from the battlefield.
There has been ____rising demand for grain as ____industrial material in spite of the nation’s good harvests.
He wondered if he could slip out of the lecture hall without anyone______.