「同位語」的用法

平時寫英文，如果有兩個或以的句子，很多人都會用 relative clause 連接，但有些情況其實是不必的，用多了反而像濫用，使句子不夠簡潔。例如：

Jonathan, who is their youngest child, is such a talented boy.

The scenery of Copenhagen, which is the capital of Denmark, will leave you breathless.

以上兩句雖然正確，但讀起來有點累贅。其實當 relative clause 帶出來的補充資料是一個 noun phrase，英文是容許把 wh-word 省略，例如：

Jonathan, their youngest child, is such a talented boy.

The scenery of Copenhagen, the capital of Denmark, will leave you breathless.

這種由兩個 nouns 或 noun phrases 並排組成的句子，文法上稱為 apposition（同位語），在英文裡是十分常見的，再舉幾個例子：

Kung Pao chicken, a traditional Chinese dish, is very popular all over the world.

Barack Obama, the first black President of the US, spent two terms in office.

They couldn't believe when the little boy stood up to Scott, the biggest bully in school.