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                                                                                                                                                  秋水
                                                                                                                                               《庄子》
        秋水时至，百川灌河。泾流之大，两涘渚崖之间，不辩牛马。于是焉，河伯欣然自喜，以天下之美为尽在己。顺流而东行，至于北海。东面而视，不见水端。于是焉，河伯始旋其面目，望洋向若而叹曰：“野语有之曰：‘闻道百，以为莫己若’者，我之谓也。且夫我尝闻少仲尼之闻，而轻伯夷之义者，始吾弗信。今我睹子之难穷也，吾非至于子之门，则殆矣。吾长见笑于大方之家。”

I often ask my music teacher____ play the piano well．

如图，直线y=kx-3与x轴、y轴分别交于点B，C， $\frac{OB}{OC}$ = $\frac{1}{2}$ .