Potential complement

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

Potential complements are a type of complement used to express the possibility (potential) of achieving an expected result.

Potential forms most commonly occur in negative statements. Affirmative statements using the potential form, when they do occur, usually give answers to questions or serve as rebuttals.

1 Formation of Potential Complements
- 1.1 Objects with potential complements
2 When to Use Potential Complements
- 2.1 Special Potential Complements
- 2.2 Use of Potential Complement or Auxiliary Verbs 可以 and 能
3 Potential Complements in Questions
4 Comparing Degree Complements and Potential Complements
5 Particles and Auxiliary Verbs with Potential Complements
6 See also
7 Sources and Further Reading
- 7.1 Books
- 7.2 Websites

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.

Result, Direction and Potential Complements
Result 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
那个美女	他	看不见

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	看不见	那个美女

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 changed 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	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.
动	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.
下	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
了	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.