_____ in prison for ten years, he seems to be unaware of what has happened outside.
During the tourist season, there are many people wandering in this city to see the old castles _____ in the sixteenth century.
_______ which way to take, the little boy behaved like a real gentleman who comforted his sister from time to time.
He doesn't know what to say, for it is the first time that he ______ with a girl.
There were many more people who got injured in the big fire than _______.
This robot is supposed to save a lot of labor, but it remains a problem if it ______.