On/Upon + V-ing ...
說明︰此句型意為“一…就…”。相當於 once 引導的副詞子句。on 後面所跟的動詞的動作執行者必須與主要子句的一致。
1. Upon reaching an appropriate age, children are encouraged, but not forced, to “leave the nest”.
一達到適當的年齡，孩子們就被鼓勵，而不是被強迫，“離開老窩”。
2. On entering the classroom, I found a book lying on the floor.
一走進教室，我就發現一本書丟在地上。
3. Upon receiving your letter, I was as happy as could be.
一收到你的信，我非常高興。
before + V-ing ...
說明︰此句型意為“在…之前”。before 後面動作的執行者，應該與主要子句中的動作執行者一致。
1. Before entering a house in some Asian countries, it is good manners to take off your shoes.
在某些亞洲的國家，進屋子之前脫下鞋子才是有禮貌的。
2. Before reading the book, you had better ask yourself if you have the time.
在讀這本書之前，你最好問問自己是否有時間。
3. Before visiting him, I called him up in advance.
在拜訪他之前，我先打電話給他。
of one’s own + V-ing
說明︰此句型意為“由某人親自所…的”。本片語為形容詞片語，置於名詞之後，做後位修飾語。
1. This is a picture of his own painting.
這是他的親筆畫。
2. This is a coat of her own making.
這是她親手做的外衣。
3. I least expected that this should be a house of his own constructing.
我怎麼也沒想到這房子是他自己造的。