把新鲜水草放在养鱼缸里的主要目的是（　　）

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Do you know what punk rock music is? I love punk rock music so much. Now let me introduce punk rock music to you. Punk rock music started in the late 1960s in U.K. Punk rock music is a way to express the singer's thought and anger with society.

      The earliest punk rock bands that formed in the early 1970s were Ramon's, Black Flag. Then in the late 1970s, more new punk rock bands were formed such as The Sex Pistols, The Clash, The Damned, Iggy Pop. Their songs were formed by some simple notes and their methods of singing were loud and they sang with anger.

      Why did punk rock music develop that fast? Because the people in that time needed some ways to express themselves. There are lots of punk rock bands nowadays, such as Distillers, The Cure, Green Day. The biggest difference between the old and newer bands is their clothing. The old punk rock bands did not really focus on their clothing, but the newer punk rock bands do focus on their clothing when they are out for functions.