A formal joining word meaning "and right after that" or "and because of that".

A formal joining word meaning "and right after that" or "and because of that"whereupon是個正式的連接詞，意思是「然後緊接著」或「因此」。

You put it in the middle of a sentence to hook a second event onto the first: "She called his name, whereupon he turned around." Two ideas live inside it, and often both at once. One is timing — the second thing happens immediately, with no gap. The other is cause — the second thing happens because of the first. In most real sentences the two blend, and you do not have to choose.

You put it in the middle of a sentence to hook a second event onto the first你把它放在句子中間，把第二件事接到第一件事後面: "She called his name, whereupon he turned around.""She called his name, whereupon he turned around."這句話 Two ideas live inside it這個字裡藏著兩個概念, and often both at once而且常常兩個同時都有。One is timing一個是時間: the second thing happens immediately, with no gap第二件事馬上發生，中間沒有間隔。The other is cause另一個是因果: the second thing happens because of the first第二件事是因為第一件事才發生的。In most real sentences the two blend在大多數實際的句子裡，這兩個意思會混在一起, and you do not have to choose你不需要特別選一個。

Notice the shape it wants: it joins two full statements, and a comma goes before it. It belongs to careful written English — news reports, history books, court judgments, formal storytelling. In everyday talk people just say "and then" or "so".

Notice the shape it wants注意它要求的句型: it joins two full statements它連接兩個完整的句子, and a comma goes before it而且它前面要加逗號。It belongs to careful written English它屬於講究的書面英文 — news reports, history books, court judgments, formal storytelling像新聞報導、歷史書、判決書、正式的敘事文。In everyday talk在日常對話裡 people just say "and then" or "so"人們就只會說"and then"或"so"。

Older writing also used it for plain "upon which" ("the table whereupon the book lay"), but that use is now rare enough that you can read it and never need to write it.

Older writing also used it for plain "upon which"較舊的寫法也會用它來表示單純的「upon which」（在……之上） ("the table whereupon the book lay")像「the table whereupon the book lay」（書放著的那張桌子）, but that use is now rare enough that you can read it and never need to write it不過這種用法現在已經少見到，你只需要看得懂，不需要自己寫出來。