完形填空

　Do you like playing the piano? Now there is a  1  in Sydney called “Play Me, I'm Yours”. People can 2  the piano in many places for free(免费). In addition to(除了……之外)letting people enjoy beautiful music, the programme  3  helps them communicate(交流)with each other better.

People have placed thirty pianos in  4  parts of the city. People can  5  the words “Play Me, I’m Yours” on each piano. People can play music  6  sing songs to the pianos. Many people stop to  7 or play happily.

Now lots of people are  8  in front of computers and busy with their work all day and they have no time to enjoy  9  . So the programme is to help them relax and make  10  friends.

依次填入下列句子空缺处的词语，最恰当的一项是（  ）
①人类的祖先在迁徙过程中    了漫长的岁月。
②人类固然不希求逢到哀苦，然而为了   人生的美好，也不应该躲避痛苦。
③老师的声音很平和，却带有一种不容   的断然压力。
④在       的林海深处，也许生长着一些不为人类所知的稀有物种。

中国古代很早就设有史官，老子就是著名的史官，而司马迁则是汉武帝时代的专职史官“太史令”。史官的设立表明  (      )

用单层棉布包紧一粒卫生球(易升华，升华形成的气体易燃)，用火柴对棉布球点火，观察到的现象及原因是(    )