441. before long (=soon)不久, 过了不久以后.
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. to sb. 向某人提起某事
450. at the mercy of (=in the power of) 任…摆布, 在…支配下
451. be in a mess 乱七八糟, 处境困难；make a mess of 弄乱, 打乱
452. bear(or keep)…in mind(=remember)牢记
453. bring(or call)to mind(=remember)使回想起
454. by mistake(由于粗心,健忘原因而)错误地
455. at the moment (=now) 此刻,现在；for the moment (=for the time being)暂时；just a moment 稍等片刻；at the last moment 在最后一刻
456. in the mood for 有情绪去做..,有心境做.
457. no more…than 和…一样都不…
458. for the most part 多半,大多数,一般来说
459. at (the) most 最多, 至多
460. make the most of 充分利用
461. be not much of(=not a good)不是很好的…；be something of 有点…,像…
462. name after 用…的名字命名
463. native to 所产的
464. by nature 天生的, 生来
465. in mature 本质上
466. (be) in the nature of 属…性质
467. none other that 不是别人,正是…
468. above normal 高于正常(温度)
469. for nothing (=free, without payment)免费
470. nothing but 只有, 不过…而已
471. to say nothing of(=not to mention)更不用说…
472. do sth. at short notice 只给很少时间准备
473. until further notice 在另行通知前
474. take notice of (=pay attention) 注意
475. object to (=be opposed to) 反对
476. objection¹ to (接动名词) 反对
477. on occasion²(=now and then)不时地,必要时
478. by occasion of (=because of) 由于
479. occupy oneself with (in) 忙于(某事)
480. it occurs to sb. that… 某人想到…