天下没有白吃的午餐。
意指任何收获都需要付出相应的代价。
Data is the new oil, and cloud computing is the new electricity.
To understand behavior, we must look at its purpose in the context of survival and adaptation.
出自孟郊《登科后》，郦波在讲解中分析了其历史背景与情感表达。