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
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