To regain their_______ after an exhausting game, the players lay in the grass.
There was so serious a matter that I had no choice but _________ the police.
The new research team was led by the ________engineer.
—Will you come?—________you promise not to invite Mary.
They ________ to enter the building by the back door; however, the front door was locked.
He _________his friend in the crowd at the first sight and called out his name.