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 look out 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 along 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)
