著、罷、出售、偷、公、假，故意、支付，相反、準

　　注：口訣中的"著"是指著火，罷指罷工，偷指偷偷地，公指出差、辦公事;假指休假，準指準時。

　　例：The house next to mine was on fire. 我鄰居的房子著火了。

　　The workers of the railway station were on strike. 鐵路工人罷工了。

　　Grapes and big water melons from Sinkiang are on sale on a large sale. 新疆葡萄和西瓜大量上市了。

　　do something on the sly (quiet). 秘密地(暗地里，偷偷地)做某事。

　　I've come here on business. 我是有公事來的。

　　They went to Bern on a mission. 他們到伯爾尼去執(zhí)行一項使命。

　　They has been away on a long trip. 他們出去做一次長途旅行。

　　I'll go home on leave next month. 下月我將休假回家。

　　I went on business to Shanghai. I did not take leave. 我是公出去上海的，不是不告面別。

　　She came to see you on purpose. 她是專程來看你的。

　　He came here on purpose to discuss it with you. 他到這來是要與你討論這件事的。

　　This lunch is on me.

　　"No. let's go Dutch."

　　"這頓午飯我付錢。"

　　"不，還是各付各的。"

　　On the contrary, it was very easy to understand. 相反，這事兒很容易理解。

　　P1ease come on time. (on schedule). 請準時來。

　　注：in time是"及時"的意思。

　　The train arrived on schedule. 火車準時到達。

　　特定時間和"一……就"，左右on后動名詞

　　例：Gases expand on heating and contract on cooling. 氣體加熱時膨脹，冷卻時收縮。(特定時間)

　　On entering the room, he found his friends dancing in high spirits. 一進屋，他就發(fā)現他的朋友們在愉快地跳舞。

　　On reaching the city he called up Lao Yang. 一到城里他就給老楊打了一個電話。

　　I'll write to him on hearing from you. 我接到你的來信就給他寫信。(一……就)

　　以及on the left, right向左向右，on the stair在臺階上等。

　　步行、驢、馬、玩笑on，cab，carriage用in

　　例：On foot步行; on horse騎馬; on donkey 騎驢。

　　He rode on, blood flowing from his side. 他騎著馬，鮮血從腰部流下來。

　　The soldier of the Eighth Route Army rode 100 li on a horse a day in order to catch up with his unit. 為趕上部隊，那位八路軍戰(zhàn)士騎馬日行百里。

　　Go on horse back! 騎馬去!

　　You are having me on! 你和我開玩笑呢!

　　in cab和in carriage 不能用on或by cab或carrige。

　　at山腳、門口在當前，速、溫、日落價核心

　　即在山腳下、在門口、在目前，速度、以……速率、溫度、在日落時、在……核心要用at。

　　例：At the foot of the mountain, there are thirty of our comrades. 在山腳下，有我們30個同志。

　　There is a beautiful lake at the foot of the hill. 山腳下有一個美麗的湖。

　　At the gate of the house there are many children playing glassball. 門口有一大群孩子在玩玻璃球。

　　Who's standing there at the door? 誰站在門口?

　　I don't need the dictionary at present. 我現在還不需要這本詞典。

　　He is at present in Washington. 他目前正在華盛頓。

　　The train runs at fifty kilometres an hour. 火車每小時行駛50公里。

　　we built the plant at top speed and minimun cost. 我們以最低的投資，最高的速度修建了該工廠。

　　at home 在國內，在家里

　　at ten degrees centigrade 在攝氏10度

　　at minus ten degrees centigrade 攝氏零下10度

　　Water freezes at 0°centigrade. 水在鑷氏零度結冰。

　　Water usually boils at 100°. 水通常在攝氏loo度沸賜。

　　at zero 在零度

　　at the rate of 45 miles an hour

　　at full speed 全速

　　at a good price 高價

　　at a low cost 低成本

　　at a great cost 花了很大代價

　　at that time 在當時

　　Evaporation takes place at all tempertures. 蒸發(fā)在任何溫度下都能發(fā)生。

　　at 1000RPM (revolution per minute) 每分鐘1000轉

　　at a high speed 高速

　　The soldiers launched an attack upon the enemy at sunset. 戰(zhàn)士們在日落時對敵人發(fā)起了攻擊。

　　at daybreak 日出時

　　The force at the core leading our cause forward is the Chinese Communist Party. 領導我們事業(yè)的核心力量是中國共產黨。

　　The atom has a nucleus at its core. 在原子的中心有一個原于核。

　　At the beginning of this term the teacher in charge of our class was very strict with us. 這學期開始，我們的班主任老師對我們要求非常嚴格。