a first course in partial differential equations偏: inclined to one side; slanti ...初等: elementary; primary; rudimen ...教程: course偏微分方程: partial differential equation; partialdifferentialequation初等微分方程第二教程: a second course in elementary differential equations下載手機(jī)詞典可隨時(shí)隨地查詞查翻譯