根据材料内容简要回答下列问题。

    Alice and John are in the music club at their school. Alice plays the violin and John plays the drums. There are two groups in the school music club: the training (训练) group and the concert(音乐会) group. Everyone starts in the training group!

     "When I first started to play the violin it sounded terrible!" Alice said. "My family asked me to practice outside."

    After a year's practice, Alice and John play much better now. They are both in the concert group and they are learning more difficult music. "We're learning the music from the film Pirates of the Caribbean. It sounds fantastic!" John said. "Playing in the club with other kids is a lot of fun."

    Playing an instrument (乐器) is not only fun. It also helps children learn to concentrate (集中注意力). "I have to concentrate when I'm practicing," Alice said. "And now it's easier for me to concentrate on my schoolwork."

    Playing an instrument can also help children become more confident (自信的). As John said, "I was scared when I played in front of a lot of people for the first time. But now I really enjoy it."

酸是一类重要的化合物，它能与许多物质发生化学反应，有比较广泛的用途．

图是我国跳水队员为迎接北京08年奥运会而刻苦训练的情景，在她离开跳板向上运动到最高点的整个过程中，关于她的动能、重力势能以及它们之间的相互转化，下列说法中正确的是（　　）

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湖泊往往成为所在城市的重要名片，风光优美，景色宜人。宋代杨万里曾写到“毕竟西湖六月中，风光不与四时同。接天莲叶无穷碧，映日荷花别样红。”宋代苏轼曾在黄州沙湖遇雨“三月七日，沙湖道中遇雨。雨具皆狼狈，余独不觉，已而遂晴，故作此词。莫听穿林打叶声，何妨吟啸且徐行。竹杖芒鞋轻胜马，谁怕？一蓑烟雨任平生。料峭春风吹酒醒，徽冷，山头斜照却相迎。回首向来萧瑟处，归去，也无风雨也无晴。”读材料，回答下列各题。

下图为某地锋面气旋示意图，据此完成各题。