Critical comments by students should be taken in a friendly spirit, accumulation of material should not stifle the student’s independence.
数学的目标是使简单的复杂化,使复杂的简单化。
薄:挑剔,贬低。訾:贬斥。贬低我商品的人,是想和我做生意;贬斥我品行的人,是想和我交朋友。