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 itself/themselves 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