题目

如图，将一根长约30cm的钢锯条紧压在桌面的边沿，使它长度的3/4伸出桌外。拨动它的顶端，可以观察到锯条在振动的同时发出声音。然后回缩一些，使它的1/2伸出桌外，再次拨动它，可以观察到锯条振动变快，并能感受到声音随之发生变化。类似实验再做几次，可以得出的结论是：。 答案：【1】振动越快，频率越大，音调越高A gentleman put an advertisement in a newspaper for a boy to work in his office. Out of the nearly fifty men who came to apply, the man selected one and dismissed(解散) the others. “I should like to know,” said a friend, “the reason you preferred that boy, who brough not a single letter—not a recommendation(介绍信）.” “You are wrong,” said the gentleman. He had a great many. He wiped his feet at the door and closed the door after him, indicating that he was careful. He gave his seat immediately to the crippled (跛的) old man, showing that he was kind and thoughtful. He took off his cap when he came in and answered my questions immediately, showing that he was polite and gentlemanly. “All the rest stepped over the book which I had purposely put on the floor. He picked it up and placed it on the table; and he waited quietly for his turn instead of pushing and crowding. When I talked to him, I noticed his tidy clothing, his neatly brushed hair, and his clean fingernails(指甲). Can’t you see that these things are excellent recommendations? I consider them more significant(明显的) than letters.” 45.  A gentleman put an advertisement in a newspaper _____ A.  in order to hire an office boy           B.  so as to dismiss the others C.  in order to select one among the fifty applicants          D.  so as to select one and dismiss the others {007} 46.  The underlined word “indicatiing” probably means _______     A.  drawing                 B.  saying                   C.  showing                 D.  speaking 47.  _______ was the very person the gentleman preferred. A.  He who had many letters        B.  He who had no letters                 C.  He who wiped his feet               D.  He who was careful,kind, polite and thoughtful 48.  According to the passage, we know that the gentleman hired the boy by________ A.  his good manners                       B.  the relationships between them                         C.  by the feelings                             D.  his letters