________the working efficiency, the boss allows the employees to have a coffee break.
..Fire safety in houses, _____ most deaths occur, is difficult to achieve.
.No matter how great the difficulty is, it can’t _____the experts from finishing the project on time.
.Whenever you enter the reading room, you can find all the students _____ at their desks, with their attention _____ on the books, except Tom.
.The little boy was found_________in his room the next day.
.—What do you think of seven o’clock outside the cinema this evening? —That _______ me fine.