442.in the long run (=in the end ) 从长远来说，最后;in the short term (从短期来说)
443.(be) at a loss 不知所措
444.major in 主修(某课程)
445.as a matter of fact 实际上，事实是
446.by all means (=at all costs) 不惜一切
(=certainly) 当然行;by means of 用……;by no means 完全不，决不
447.on memory of 为纪念……
448.on the mend (=in the process of recovering) 好转，在康复中
449.mention sth. sb. 向某人提起某事
450.at the mercy of (=in the power of ) 任……摆布，在……支配下
