401. instead of (=in place of) 代替，而不是…

402. instruct…in (=teach) 教.指导.训练某人…

403. insure…for 把…保险(多少钱); ensure 使安全; assure…(of) 使…确信,保证

404. insure…against 保险…以防

405. intend…for 打算把…给

406. (be) intent on 专心致志, 坚决

407. in the interests of 符合…的利益 be interested in 对…感兴趣

408. interfere in干涉, interfere with打搅,干扰

409. at intervals 每隔一会儿, 每隔一段距离

410. intervene in 干预

411. invest in 投资

412. be involved in (=become connected or concerned) 卷入, 参加

413. by itself (=alone, without help)单独地,靠自己

414. in itself 本身; of itself 自发,自然

415. be jealous of 妒忌

416. jump at (=to be eager to accept)抢着接受,

417. jump on (=scold, tell of) 叱责

418. junior to sb. 年纪较…轻, 职位较…低.

419. (be) keen on 喜爱, 渴望

420. keep a close watch on ( =keep a sharp lookout for) 密切注视

421. keep…to oneself(=keep secret)不告诉别人

422. to(the best of) one’s knowledge 据…所知

423. at large(=at liberty, free) 在逃, 逍遥法外 at large(=in general) 一般来说, 大体上 at large(=at full length; with details)详细地

424. lean against (背)靠着…

425. at least 至少; at most 至多

426. (not) in the least 一点(也不), 丝毫(也不)

427. at one’s leisure 在…有空的时候

428. lend itselfthemselves to适合于(某用途)

429. at length (=after a long time, at last)终于 at length (=in detail, thoroughly)详细地

430. go to any length想一切办法, 尽一切力量

431. be liable to (=be subject to)易于..的,应受(罚)

432. be liable for 对…应负责任的

433. lie in 在于

434. in life 一生中

435. for life 终身

436. in the light of (=considering; taking into account) 考虑到, 根据

437. throw light on ( = make clear, explain) 使…更为清楚, 提供线索, 阐明

438. in line with(=in aGREement with)符合,一致

439. long for(=want very much)渴望,希望得到

440. for long 很久,很长时间(否定句.疑问句中)

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. objection to (接动名词) 反对

477. on occasion(=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…

481. once and for all =once and forever永远地 all at once (=suddenly, now) 立即,马上 once in a while (=occasionally) 偶尔 (just) for once 就这一次

482. (all) by oneself 独自(没有别人帮助)

483. operate on sb. 给某人做手术 operation n. come go into operation开始运转 putbring sth. into operation 使…投产,运转

484. be of the opinion 持有…的看法

485. in one’s opinion 按某人的看法

486. be opposed to… 反对…

487. be opposite to 与…相反的

488. (be) in order(=acceptable)合适的,恰当的 in order 井井有条,处于良好状态; out of order(=in bad condition)出毛病,发生故障

489. made to order 定做的(衣服)

490. originate infrom(=begin)起源于,由..引起

491. on the outskirts (of) 在城郊

492. owe…to 把…归于…

493. on one’s own (=along, without help)单独

494. of one’s own某人自己的

495. keep pace with 跟…齐步前进

496. go to GREat pains=take pains 下功夫,努力

497. part with (=give up, sell) 舍弃,卖掉

498. participate in (=take part in)参加

499. (be) particular about 讲究,挑剔(吃,穿)

500. in particular (=especially) 特别是,尤其