18.In this experiment, they are woken up several times during the night, and asked to report what they _______.
The black horse is _____ of the pair .
______ professional violinist practises for several hours a day , but ______ violinist has his own way of playing the Beethoven concert .
Mr Zhang gave all the textbooks to all the pupils , except _____ who had already taken them .
Shortly after the accident , two ______ police were sent to the spot to keep order .
My dictionary ________ . I have looked for it everywhere but still ______ it .