英语语法: Adverbial Complement 状语补足语vs. Adverbial Adjunct状语附加语
Source: Zhihu
(prepared by: alexcwlin; edited by: Adam Lam)

Question:
A reader asked me to look at the following:

1.     Adverbial Complement: River is flowing through the vast flood plan.

2.     Object Complement or Adjunct: Government is considering a new law in the winter session.

3.     Adverbial: They were shouting in the forest.

A.    第一个例句黑体字部分是adverbial complement 第三句黑体字部分是adverbial.
如何区分这两个概念呢

B.    另外，Object complement是用来补充说明宾语的，那adverbial complement是不是也可以理解成补充说明adverbial，如果是这样的话，那么第一个例句的adverbial是什么呢？请指点因为我看过很多中文语法书，里面还没有出现“状语补足语”，这个术语翻译得对吗？

alexcwlin comments:

By definition, an Adverbial Complement is an essential Adverbial modifying a Verb in a sentence. (Note 1, 2 & 3)

In contrast to an Adverbial Complement is an Adverbial Adjunct, which is a non-essential Verb-modifying Adverbial in a sentence without which the sentence’s structure or meaning would not have been altered. (Note 4)

To answer your questions:

A.    An Adverbial Complement actually is a type of Adverbial (Note 5).

In “River is flowing through the vast flood plan”, the Adverbial Complement “through the vast flood plan” is essential to perfect the meaning of the sentence.

If you take it away, the sentence would become “River is flowing” and the meaning would have completely changed.

Therefore “through the vast flood plan”, being essential to the sentence and modifying the Verb, meets the condition to be an Adverbial Complement.

In #3, “They were shouting in the forest”, “in the forest” simply is an “Adverbial” (or more specifically a “Prepositional Adverbial Phrase”) modifying the Verb “were shouting” in telling where the “shouting” happened. While “in the forest” is an Adverbial, it is also essential to the meaning of the sentence. Therefore, the phrase “in the forest” is an Adverbial and an Adverbial Complement at the same time.

“Adverbial Complement” and “Adverbial” are not exclusive concepts, i.e., a phrase can be both an “Adverbial Complement” and an “Adverbial” at the same time, because “Adverbial Complement” is a type of “Adverbial”.

B.    You ask while an Object Complement modifies an Object, shouldn’t an Adverbial Complement modify an Adverb following the same logic?

The answer is “no”.

An Adverbial Complement modifies a Verb, not an Adverb. As much as it is inconsistent, that’s the way it is and there is no logical explanation for that.

In fact in other areas, a Subject Complement modifies a Subject, and an Adjective Complement modifies an Adjective, along the same line as an Object Complement modifying and Object.

Notes:

1.     The dictionary definition of “complement” is “something that completes or perfects”.
For Wiki explanation of Adverbial Complement, see: https://en.wikipedia.org/wiki/Adverbial_complement#:~:text=An adverbial complement is an,different meaning of the verb

2.     Normally an Adverbial Phrase modifies a Verb, an Adverb or an Adjective.
But in the case of an Adverbial Complement, it modifies a Verb only, and not an Adverb or an Adjective.

3.     “Essential” means without the Adverbial Complement, the sentence would mean differently, or it may even become ungrammatical.
For example, in “She put the book back”, “back” is the Adverbial Complement modifying the Verb “put”. But if you leave it out, the sentence would become “She put the book” which doesn’t make sense. Therefore, the Adverbial Complement is essential to complete the meaning of the sentence.

4.     “Adjunct” means “extra”.
In “Stubbornly, the suspect refused to cooperate with the police”, “stubbornly” is an Adverbial Adjunct. If it is removed, the sentence becomes “The suspect refused to cooperate with the police” which is still grammatical and the structure would not have changed much.

5.     An Adverbial is an Adverb or an Adverbial Phrase

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