____is known to all, good friends _________ happiness and value to life.
The chairman thought necessary to invite Professor Smith to speak at the meeting.
The ability _____ an idea is as important as the idea itself
—What do you think we can do for our aged parents? —You ____ do anything except to be with them and be yourself.
— Have you got any particular plans for the coming holiday? — Yes, _____, I’m going to visit some homes for the old in the city.
Eye doctors suggest that a child’s first eye exam____at the age of six months old.