非限定用法~~~~~?

Sam bought the novel which is famous.

這裡用的是「限定用法」的修飾語，which/that ...前面不用逗號隔開。

the xxx = that one 

Sam買了"那"本有名的小說。

因為受到修飾語（後面的形容詞子句）的限定，普通名詞novel前要用「定冠詞」the。

Sam bought a novel, which is famous.

這裡用的是「非限定用法」的修飾語，是逗號＋which....

a xxx = any one

Sam買了一本小說，那本小說很有名。

要用「不定冠詞」a/an，因為普通名詞novel未受到限定。不可用定冠詞the。

1，我認為本句多解釋結果適得其反，這句關鍵在逗號所引導子句或片語等，只是对其先行詞做一描述不影響句意，可以給予另一名稱"插入句"，我們按此原則，本句以Sam bought the novel, which is famous.較佳

2，我拿另一句子就需用限定用法，The girl who lives in Paris is my younger sister. 因為他有幾位姊妹，而指定其中一位住巴黎的妺妹

3，至於加不加由主觀判断，不若过去分詞以very加入來判斷是形容詞或動詞，例I am(very) interested in studying foreign language. 可知是形容詞

Sam bought the novel, which is famous, is very cheap(=costing little money;low in price,ie:-for a low price.).

The adj cl in the statement is non-defining clause. There is a comma before and after each. the adj cl. only adds additional information to "the novel"because there are no other novels. 可有可無 Without this adj cl., the meaning of the sentence is still complete, known as a non-defining clause.

不可以

因為先行詞"novel"不具有單一或獨特性

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單一性

例如:Taipei 101，這世界上就只有一棟101，所以101具有單一性

獨特性

例如:grandfather's gold watch，爺爺可能擁有不只一隻金錶，但可以知道是爺爺的，所以grandfather's gold watch具有獨特性

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具有以上兩種特性其一才可使用非限定用法

Just say:

I bought a famous novel.   (that is it, period)

**example to use relative clause:

I bought the novel that you recommended.