一天，有位中国姑娘对我说，按照传统风俗习惯，孩子的婚姻必须由父母做主，因此她母亲的婚姻是由她祖父安排的，不过，她姐姐却打破了这个惯例。

marriage was arranged by her grandparents,but her sister has broken the tradition.

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比方说，人与人之间的正式关系，你是可以按照久已存在的风俗习惯来决定的。

For example, formal relationships among people may be determined according to customs and habits that have existed for a long time.

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