题干

下列各图描述的实验中,用来说明声音的传播需要介质的是(   )

A:发声的音叉激起水花

B:音叉发出的声音越响,乒乓球被弹开的越远

C:钢尺伸出桌边的长度变短,振动时声音的音调变高

D:抽取玻璃罩内的空气,听到罩内的音乐声减小

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D

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阅读理解

    Many musicians meet and form a band(乐队)because they like to write and play their own music.They may start as a group of high school students and practise their music in someone's house.Sometimes they may play to passers-by in the street or underground so that they can get some money for themselves or pay for their instruments(乐器).

    However,there was one band that started in a different way.It was called the Monkees and was formed in 1965.It began as a TV show.The TV show had planned to find four rock musicians who could act as well as sing.But they could only find one who was good enough.They had to use actors for the other three members of the band.

    Since some of these actors could not sing well enough,they had to ask for help from other musicians.So at first,the band just pretended(假装)to sing.Anyway,their performances(演出)were excellent and they got lots of fans.Each week on TV,the Monkees would pretend to play and sing songs written by other musicians.After a year or so,they became more serious about their work.They started to play and sing their own songs like a real band.Then they produced(制作)their own records and started touring and playing their own music.In the US they became even more influential and popular than the Beatles and sold even more records.

    However,the band broke up around 1970.But happily they reunited(重聚)in the 1980s.They produced a new record in 1996 to celebrate their time as a band.It was very successful.Today the Monkees are still making music for their millions of fans.

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