英语语法: 介词短语作主语
Source: zhihu
(prepared by alexcwlin; edited by: Adam Lam)

Question:
In my translation of 0701翻译：在山的那边(王家新), there are two sentences which read like this:

1.     But I came back almost in tears, because the other side of the mountain was still more mountain.

2.     On the other side of the mountain is indeed the “sea”

A reader asks:

Hi, Adam . 请问第一句是不是缺少了一个介词On呀，because the other side of the mountain was still more mountain. On the other side of the mountain is indeed the “sea”.

第二句又有了on，是漏了吗，还是就有这个用法呢

alexcwlin comments:

In the first sentence “…the other side of the mountain was still more mountain”, “the other side of the mountain” is a Noun Phrase (with “the other side” as the Main Noun Phrase and “of the mountain” as the Prepositional Adjectival Phrase).
[在第一句“…the other side of the mountain was still more mountain”中，“the other side of the mountain”是一个名词短语(“the other side”是主要名词短语，“of the mountain”是介词形容词短语)。]

Yes, you can add the Preposition “on” and rewrite the phrase as “on the other side of the mountain was still more mountain” with the Prepositional Phrase “on the other side of the mountain” functioning as the Noun Subject of this clause.
[是的，你可以加介词“on”，把这个短语改写为“on the other side of the mountain was still more mountain”，介词短语“on the other side of the mountain”作为这个从句的名词主语。]

A Prepositional Phrase can function as the Noun Subject of a sentence. (see my grammar notes Prepositional Phrase on “Inverted Sentence” at: https://zhuanlan.zhihu.com/p/92696102 and also https://parentingpatch.com/using-prepositional-phrases-subjects/)
[介词短语可以作为一个句子的名词主语 (看我的文法笔记介词短语在“倒装句”上的用法: https://zhuanlan.zhihu.com/p/92696102 并且https://parentingpatch.com/using-prepositional-phrases-subjects/)

That answers your second sentence that in “On the other side of the mountain is indeed the ‘sea’ ”, the Prepositional Phrase “on the other side of the mountain” serves as the Noun Subject of the sentence.
[这就回答了你的第二句“On the other side of the mountain is indeed the ‘sea’”，介词短语“on the other side of the mountain”作为这个句子的名词主语。]

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