Potential complement

Also known as: 可能补语 (kěnéngbǔyǔ)  and complements of potentiality .

Potential complements are a type of complement used to express the possibility of achieving an expected result in Mandarin.

Potential forms most commonly occur in negative statements. Affirmative statements using the potential form are somewhat uncommon, and, when they do occur, are usually answers to questions (or as rebuttals).

Formation of Potential Complements

For affirmative potential complements, 得 is placed between the action verb and the complement. For negative potential complements, 不 is placed between the action verb and complement. The structure of the potential form is:

V + 得/不 + complement

Putting 得 or 不 between an action verb and a result complement or direction complement changes them to potential complements.

Resultative, Directional and Potential Complements

Resultative Complement	Directional Complement	Aff. Potential Complement	Neg. Potential Complement
做 完		做 得 完	做 不 完
听 懂		听 得 懂	听 不 懂
	起 来	起 得 来	起 不 来
	爬上来	爬 得 上来	爬 不 上来

Objects with potential complements

Objects in sentences with potential complements can occur either after the complement or at the beginning of a sentence

Objects occurring at the beginning of a sentence with a potential complement

Object	Subject	Complement Phrase
这个汉堡	我	吃得完
山	他	爬不上来

Objects occurring at the end of a sentence with a potential complement

Subject	Complement Phrase	Object
我	吃得完	这个汉堡
他	爬不上来	山

When to Use Potential Complements

The potential complement is roughly equivalent to saying something is able to be done in English. It is used when you want to express ability to achieve a result (as noted above, a [result complement] can be change into a potential complement be inserting 得 or 不 between the verb and the complement) or ability to perform an action to a certain degree, similar to degree complements. Degree complements and potential complements often appear the same but are distinguished by the different contexts they appear in (see Contrasting Degree and Potential Complements section below).

Special Potential Complements

In addition to common result complements that can be turned into potential complements and adjectives that form either degree or potential complements there are several complements that have unique meanings as potential complements.

Special Potential Complements

Complement	Example Complement Phrase	Example Sentence	Explanation
动	走不动了	我们累死了，走不动了。 (We are so tired, we can't (don't have the strength to) walk any more.)	The potential complement 动 indicates whether a person has the strength to be able to undertake an action whether that be moving them self (walking further) or an object.
	抬得动	她力气很大，她抬得动这张沙发。(She is very strong, she can lift this sofa.)
下	坐得下	这间大房子，坐得下十个人。(This big room can seat ten people)	The potential complement 下 expresses the ability to fit in or on a given location.
	放不下	那个包，放不下这些西瓜。(That bag cannot fit these watermelons)
了	受不了	今天天气太热了，我受不了了。(Today it is too hot, I am unable to bear it)	The potential complement 了 expresses the ability do the verb. Note: 了 can also serve as an adjective complement which means ability to reach a degree
	来得了	今天开会我来得了。(I am able to come to today's meeting)

Use of Potential Complement or Auxiliary Verbs 可以 and 能

In most cases simple potential complement phrase will have the same meaning as a verb phrase using auxiliary verbs 能 or 可以. For example, 他爬得上来 has the same meaning as 他能爬上来 and 他可以爬上来. Likewise 我能做完, 我可以做完 and 我做得完 all have the same meaning.

Potential Complements in Questions

You can form questions with sentences containing result complements just as you would with any other sentence:

• With a question particle
• With a question word
• With Positive-negative inversion

Some examples:

• 你 做得 完 吗 ？
• 你 受不 了 吗 ？

• 谁 吃得 完 整只 鸡 ？
• 你 考得 上 什么 大学？

• 那间 房子 坐得 下 坐不 下 十个人？
• 明天的音乐会 你 来得 了 来不 了？

Contrasting Degree and Potential Complements

Some sentences that contain adjective complements may be indistinguishable as degree or potential complements when they are taken out of context. For example 跑得快 or 说得清楚 could serve as either potential or degree complements. The following scenarios put these examples in a context and distinguish them as potential and degree complements.

Potential Complements

A:他跑得快，跑不快？

B:他跑得快。

A:她能说得清楚吗？

B:他说不清楚。

Degree Complements

A: 我的朋友跑得很快，他呢？

B:他跑得快。

A:她说得清楚还是说得不清？

B:她说得清楚。

Degree complements commonly are directly preceded by an adverb (他说得很清楚) distinguishing them from potential complements which are never directly preceded by an adverb.

Particles and Auxiliary Verbs with Potential Form

• Aspect particles 了, 着, and 过 never occur after a verb with a potential complement, they may however occur after a potential complement phrase (after the complement).
• Auxiliary verbs of possibility (可能, 可以, etc.) can be used in an affirmative potential complement statement and do not change the meaning of the sentence. They do not occur in negative potential complement sentences.

Sources and Further Reading

Books

• Integrated Chinese, Level 2 Part 2 Lesson 12 (no affiliate link)

• Modern Mandarin Chinese Grammar: A Practical Guide pages 191-194

• 外国人实用汉语语法(中英文对照) pages 317-330

Websites

• Centre for Teaching Chinese as a Foreign Language, University of Oxford: Potential Verb Complement

• Mandarin Essential Grammar, Center for Language Study, Yale University: The Potential Complement

• About Chinese Language, XCN chinese Potential Complement (2)