A man knows when he is growing old because he begins to look like his father.
当一个人开始长得像他的父亲时，他就知道自己正在变老。
The language of mathematics is universal, transcending cultural and linguistic barriers.
材料的使用方式有其政治性。
纪律是目标与成就之间的桥梁。
孩子们喜欢安静和自由选择。