on
on a diet(在节食), on a picnic, on a trip, on a vacation trip, on a visit, on a voyage, on a walk, on approval, on bended knees(跪着) on business, on call (待命) on credit(赊帐), on display, on drill(在训练), on duty, on exhibition, on fire, on foot, on good terms(友好), on guard, on hire(出租) on holiday, on leave, on loan(出借), on offer(出售中), on one’s day(在最兴旺的日子), on one’s guard(警惕) on one’s honeymoon, on one’s knees, on one’s mind(惦念), on one’s own time(在非工作时间), on one’s round(出诊) on order(已订购), on parade(在游行), on patrol(巡逻) on sale(待售) on sale, on show, on stream(在生产中) on the air(在广播), on the alert(提防), on the ebb(在退潮), on the feed(在进食), on the fly(在飞行中), on the increase/decrease(在增长/下降中), on the job(工作着) on the listen(在注意听), on the lurk(暗中行动), on the march(行军中), on the move(在活动中) on the phone(在打电话) on the quiet(秘密地) on the rise(在上涨), on the run(跑这), on the spot(在危险中，当场), on the strike, on the turn(在转变中) on the watch(守侯着), on the way(在途中), on the way, on tour, on trial, on vacation, on view(展览着), on watch(值班),
at
at a disadvantage(处不利地位), at a lecture, at a run(跑着), at breakfast, at call(随叫随到), at church, at dinner, at ease(悠闲自得), at feed, at gaze, at grass， at graze,(在吃草) at hand(在手边), at high/low(处于高潮/低潮中), at issue(在争论中), at large(未被捕), at leisure (空闲着), at meals, at peace, at play, at rest, at school, at stake(处在危险中), at study, at table(在吃饭), at the bar(受到公开审问), at the meeting, at the piano, at the wheel(在驾车), at war, at work
