雅思介词用法口诀讲解
着、罢、出售、偷、公、假，故意、支付，相反、准
注：口诀中的着是指着火，罢指罢工，偷指偷偷地，公指出差、办公事;假指休假，准指准时。
例：The house next to mine was on fire. 我邻居的.房子着火了。
The workers of the railway station were on strike. 铁路工人罢工了。 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 . 秘密地做某事。
Ive come here on business. 我是有公事来的。
They went to Bern on a mission. 他们到伯尔尼去执行一项使命。
They has been away on a long trip. 他们出去做一次长途旅行。
Ill go home on leave next month. 下月我将休假回家。
I went on business to Shanghai. I did not take leave. 我是公出去上海的，不是不告而别。
She came to see you on purpose. 她是专程来看你的。
He came here on purpose to discuss it with you. 他到这来是要与你讨论这件事的。
This lunch is on me.
No. lets go Dutch.
这顿午饭我付钱。