因果推理需要仔细思考分析背后的假设。
"Causal inference requires careful thought about the assumptions underlying your analysis."
All happy families are alike; each unhappy family is unhappy in its own way.
能源行业是任何经济的支柱，其稳定性保障国家安全。
我越是研究染色体，就越意识到它们非凡的行为。
Every body continues in its state of rest, or of uniform motion in a right line, unless it is compelled to change that state by forces impressed upon it.