Historical experience can as a most important source of information.
---Are you kind enough to open the door for me?---_________________.
The dog had such ______ to his master that it would not leave him, even when he was dead.
---who______it be that is knocking at the door? ---It_______be Father, but I’m not sure.
Though _____ of the danger of hiking in such weather, the young men still wouldn’t give up their plan.
The detective, __________ to be reading a newspaper, glanced at the man seated next to a woman.