I'vetowaithereuntilthelecturerarrives.A.beinginstructedB.beeninstructedC.instructedD.instruct2.Manypeopleareagainstnewdrugsonanimals.A.betestedB.beingtestedC.testD.tested3.WhenIenteredtheroom,everyonew

Question

I've___to wait here until the lecturer arrives.
A.being instructed   B.been instructed   C.instructed   D.instruct

2.Many people are against new drugs___on animals.
A.be tested   B.being tested   C.test   D.tested
3.When I entered the room,everyone was laughing___.
A.clearly    B.mournfully   C.sadly   D.loudly
4.They have lauched a man-made satellite___.
A.success   B.succeed   C.successfully   D.successful
5.We must work hard to___a good knowledge of English.
A.read   B.study   C.acquire   D.learn
6.Jill smiled___because he didn't know how to help his friend.
A.sympathetically   B.happily   C.loudly   D.continuously
7.The little boy___his mom when he heard her laughing.
A.turned attention to   B.turned his attention to   C.paid attention on   D.paid his attention on
8.We___the fallen tree away from the road.
A.made   B.took   C.brought   D.dragged
9.They___around for hour,looking for their son.
A.would wander   B.were wandering   C.wandered   D.have been wandering
10.She suddenly___after she heard of the accident.
A.broke tears   B.broke in tears   C.broke out tears   D.broke into tears

Answer 1

1、选C
音量不变是指声音的大小即响度不变,快速播放同一段录音,发出声音的振动频率加快,声音的音调变高．所以C正确
2、选D
A、老师用扩音器讲课,增大了声音的响度,不是改变音调；
B、摩托车上装消音器,在声源处减弱了噪声,不是改变音调；
C、用大小不同的力敲击同一个音叉,振幅不一样,声音的响度不一样,不是改变音调；
D、依次敲击装有不同高度水的瓶子,瓶子振动的快慢不一样,声音的音调不同,正确.
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