As a teacher, I seldom give my students so difficult a problem_______ they can’t work out.
With his attention _________ on his book, he didn’t notice someone entering his room.
They have earned lots of money, so I______ believe that the business is a success.
Sales director is a position_______ communication ability is just as important as sales.
The statistical figures in that report are not_______. You should not refer to them.
As nobody here knows what is wrong with the machine, we must send for an engineer to _______ the problem.