15．D.the number of表示“--的数目 .而a number of表示“许多-- . 100 Mr. Robinson had to travel somewhere on bu——青夏教育精英家教网—

15．D.the number of表示“--的数目 .而a number of表示“许多-- . 100 Mr. Robinson had to travel somewhere on business, and as he was in a hurry, he decided to go by 1 . He liked sitting 2 a window when he was flying, so he got onto the plane, he looked for a window seat. He 3 all of them taken except one. There was a young man 4 beside it, and Robinson was surprised that he had not taken the one by the window. Anyhow, he went towards it. When he 5 it, however, he saw that there was a notice on it, written 6 large letters, 7 “This seat is kept for proper balance. Thank you. Mr. Robinson had never seen such a notice before, but he thought the plane must be carrying something particularly heavy in its room 8 made it necessary to have the passengers properly balance. So he walked on and found 9 empty seat, not beside the window 10 . Two or three other people 11 to sit in the window seat next to the young man, but they also read the notice and went on. Then when the plane was nearly 12 a very beautiful girl 13 into the plane. The young man, who was watching the passengers coming in, 14 took the notice 15 the seat beside him, and by this means succeeded in having a pretty companion during the whole trip. 【查看更多】

There are 　　books on the shelf. And 　　　 them is about three hundred.