真正的挑战不在于解方程,而在于理解解的含义。
The real challenge is not in solving the equations, but in understanding what the solutions mean.
对来自学生的批评应该本着友好的精神来接受,学习材料的积累不应该扼杀学生的独立性。
The future of forestry lies in technology, but it must serve nature, not exploit it.