解释下列词语

①锋利

②绝望

短文改错

本文中共有10处语言错误,每句最多有两处.错误涉及一个单词的增加,删除和修改.增加:把缺词处加一个漏字符号(∧),并在其下面写出该词.删除:把多余的词用斜线(＼)划掉.修改:在错的词下划一横线,并在该词下面写出修改后的词.注意: 1.每处错误极其修改均限一词.2.只允许修改10处,多者从第11处不记分.

    Mr. Smith had a 8-year-old son named Tony, who enjoyed listening to music very much. So he bought a piano to Tony, hoping that he can become a famous pianist one day. The little boy put her heart into practising the piano day after day and seemed enjoy every minute of it. However, half a year later, he told his father that he was tiring of practising the piano. Heard this, Mr. Smith said, “Tony, it is one thing to be fond of listen to music, but it is another thing to perform skillful by yourself. You can never play the piano well even if you don't practise more.”

如图，是一个长方体的三视图（单位：cm），这个长方形的体积是____ cm³．