题干

下列各项有关控制噪声的具体措施中,属于控制噪声声源的措施是____;属于阻挡噪声传播的措施是____;属于防止噪声进入人耳的措施是____。(填序号)

A.城市市区禁鸣喇叭  B.纺织女工带上耳塞  C.城市高架桥上安装隔音墙  D.在噪声车间内安放吸声材料  E.汽车安装消声器  F.开战斗机的飞行员戴上头盔  G.点燃爆竹导火线后捂住耳朵

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A E,C D,B F G

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    Mom was a teacher most of her life. When she wasn't in the classroom, she was educating her children or grandchildren: correcting our grammar; starting us on collections of butterflies, flowers or rocks; or inspiring a discussion on her most recent “Book of the Month Club” topic. Mom made learning fun.

    It was sad for my three brothers and me to see her illness in her later years. At eighty-five, she suffered a stroke(中风) and she went steadily(不断地) downhill after that.

    Two days before she died, my brothers and I met at her nursing home and took her for a short ride in a wheelchair. While we waited for the staff to lift her limp body back into bed, Mom fell asleep. Not wanting to wake her, we moved to the far end of the room and spoke softly. Several minutes our conversation was interrupted by a muffled sound coming from across the room. We stopped talking and looked at Mom. Her eyes were closed, but she was clearly trying to communicate with us. We went to her side.

    “Whirr,” she said weakly.

    “Where?” I asked. “Mom, is there something you want?” “Whirr,” she repeated a bit stronger. My brothers and I looked at each other and shook our heads sadly.

    Mom opened her eyes, sighed, and with all the energy she could gather said, “Not was, say were!”

    It suddenly occurred to us that Mom was correcting brother Jim's last sentence. “If it was up to me…”

    Jim leaned down and kissed her cheek. “Thanks, Mom,” he whispered. We smiled at each other and once again shook our heads…this time in awe (敬畏) of a remarkable teacher.