—Who ________ it be that is knocking at the door?—It________ be Mother, but I’m not sure.
The library needs __, but it will have to wait until Sunday.
Having passed all the tests, she felt a great weight _____ off her mind.
New ideas sometimes have to wait for years before _____.
Seeing the soldiers well _____ for the flood-fight, the general nodded with satisfaction.
He looked around and caught a man _____ his hand into the pocket of a passenger.