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. 1 in干涉, interfere with打搅,干扰
409. at 2 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 3 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)
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