It happens that I am quite familiar with the professor _______ to give us a speech on environmental protection next Monday.
Somehow, the old man had ________ a dangerous secret, one which could not be discussed in a room on a military base.
We recently did a simple experiment, which happens to ________ how children's knowledge of what a hero is like determines their behaviour.
To the surprise of the manager, Mrs. Black, who is not easy to deal with, quickly ________ and accepted the new work schedule.
The actress readily ________ the fact that her unbalanced diet was a major influence on her expanding figure.
Not having promoted the new digital camera successfully, the company should ________ its original marketing methods.