23.It is______ you’re tired; you’ve been walking for hours.
_____, I couldn’t find a solution to the problem.
The meeting was _____ when the chairman fell ill.
The members of the club wouldn't run a _____ in entrusting(委托) the organization to an unreliable person.
Many new _____ will be opened up in the future for those with a university education.
It isn't quite _____ that he will be present at the meeting.