Inflection (Accidence)  

What is inflection?

Grammatical inflection (sometimes known as accidence or flection in more traditional grammars) is the way in which a word is changed or altered in form in order to achieve a new, specific meaning.
Verbs are the most commonly inflected words, changing form to reflect grammatical tense, as well as mood, voice, aspect, person, and speech. Collectively, this is known as conjugation.
The other parts of speech that can undergo inflection are nouns, pronouns, adjectives, and adverbs. These are categorized collectively under the term declension.
Most inflection is done according to consistent rules and patterns, but, as we’ll see, there are many words that are irregularly inflected.
We’ll look at the basics of conjugation and declension below, and then briefly discuss regular vs. irregular inflection. Continue on to the individual sections to learn more about them in greater detail.


As we noted above, conjugation refers specifically to the inflection of verbs.


When we discuss conjugating verbs, we are usually referring to how a verb changes according to tense—that is, when an action happened in time. Verbs in their basic form are naturally in the present tense (specifically known as the present simple tense). For example:
  • “She walks to work.”
  • “We live in the city.”
  • “They work too hard.”
  • “He sings for an hour each day.”
Verbs can only be truly inflected for the past tense (specifically the past simple tense). Most verbs are changed by adding “-d” or “-ed” to their end (which also forms their past participle form). However, many verbs are considered irregular and have past tense and past participle forms that cannot be predicted. For example:
  • “She walked to work.” (regular verb)
  • “We lived in the city.” (regular verb)
  • “He sang for an hour each day.” (irregular verb)
Using auxiliary verbs and verb participles, we can also create the continuous, perfect, and perfect continuous forms of either the past or present tense. For instance:
Finally, we can also form an approximation of the future tense. Verbs do not have a specific form to reflect future action, so we use other verb constructions to achieve this meaning, usually the modal auxiliary verb will, as in:


Grammatical aspect is concerned with how an action, state of being, or event occurs in time; we use it with tense to create specific forms of verbs in relation to time.
Each verb tense has four aspects, or temporal structures: the simple, the perfect, the continuous, and the perfect continuous. These coincide with the different verb tenses we looked at above. When we form the present continuous tense (“I am walking”), for instance, we are actually using the continuous aspect of the present tense.


Most of the time when we speak or write, we are discussing or asking what is true, real, or actually happening. This is known as the indicative mood. For instance:
  • “I ate breakfast at 3 o’clock.”
  • “We are going swimming this afternoon.”
  • “Will they be there tonight?”
When discussing an unreal, hypothetical, or desired situation, we use what’s known as the subjunctive mood. This is usually marked by shifting the verb into the past tense, as in:
  • “I wish it was/were* Saturday.”
  • “If I had a million dollars, I would move to the Bahamas.”
(*Traditionally, the verb be always conjugates to were in the subjunctive mood, regardless of the plurality of the subject of the sentence. However, it is becoming common in modern English to use was if the subject is singular.)
When we make direct commands to someone, we use what’s known as the imperative mood to form imperative sentences. They have no subject (it is implied), and the verb is in the base or bare infinitive form. For example:
  • Close that window!”
  • Sit down, please.”


Voice has to do with the relationship between a verb and its source of agency—the person or thing performing or controlling the action of the verb. This is usually the subject of the sentence or clause, which is known as being in the active voice. For instance:
  • He wrote the book.”
  • The Millers are preparing dinner.”
We can also construct sentences in which the subject of the sentence is not the agent of the verb, but rather the object of its action. If the agent is identified, it is only in a prepositional phrase at the end of the sentence. This is known as passive voice. For example:
  • The book was written (by him).”
  • Dinner was prepared (by the Millers).”

Grammatical person

Grammatical person refers to whether the subject is the speaker or writer (first person), someone being directly addressed (second person), or a person or thing that is being spoken or written about (third person). Each of these can be either singular or plural.
Almost all verbs are conjugated a specific way only if the subject is in the third person, is singular, and is in the present tense. We do so by adding an “-s” or “-es” to the end of the verb, as in:
  • I walk everywhere.” (first-person singular)
  • She/he/it walks everywhere.” (third-person singular)
The exception to this is the verb be, which has several unique conjugations for grammatical person and tense. For example:
  • I am outside.” (first-person singular, present tense)
  • She/he/it is outside.” (third-person singular, present tense)
  • I/she/he/it was outside.” (first/third-person singular, past tense)
  • You/we/they are outside.” (first/second/third-person plural, present tense)
  • You/we/they were outside.” (first/second/third-person plural, past tense)


Grammatical speech refers to the quotation of or reference to something said or written by someone else. We typically indicate this by shifting a “reporting” verb (said, told, ask, etc.) into the past tense.
When we say exactly what someone said (known as direct speech or direct quotation), we use quotation marks, as in:
  • Mary said, “I want to have another baby,” which took him by surprise.
When we are only paraphrasing or summarizing what someone said, it is known as reported or indirect speech, and we do not use quotation marks. For example:
  • Mary told me that she hadn’t been serious.


While conjugation only deals with the inflection of verbs, declension covers the inflection of nouns, pronouns, adjectives, and adverbs.

Declension of nouns

Generally, we only decline nouns to mark plurality—that is, whether there is more than one person, place, or thing being discussed. We usually do so by adding an “-s” or “-es” to the end of the noun, as in books, watches, toys, cars, etc. There are a few other spelling patterns that apply, and there are a number of irregular plurals that do not follow any conventions at all—go to the section on Plurals to learn more.
We can also decline certain nouns to reflect gender, as in prince (masculine) vs. princess (feminine). However, the majority of nouns in English are not inflected for gender.

Declension of pronouns

For the most part, only personal pronouns are subject to inflection. We decline personal pronouns based on grammatical person, number, gender, and case. The pronouns who and whoever can also be declined to whom and whomever to reflect the objective case; however, this is becoming less common in everyday speech and writing.
The table below provides a quick breakdown of the various personal pronouns. (Reflexive pronouns, though not technically a type of personal pronoun, are so closely related in form that they have been included as well.) Continue on to the Declension chapter or go to their individual sections in the chapter on Personal Pronouns to learn more about how they are formed and when they are used.
Subjective Case
Objective Case
Possessive Determiner
Possessive Pronoun
Reflexive Pronoun
First Person
First Person
Second Person
Yourself (Yourselves if plural)
Third Person
Third Person
Third person
Its (own)
Third person
Neuter (Gender Neutral)

Declension of adjectives and adverbs

We decline both adjectives and adverbs in the same way to create comparative and superlative forms. As the name suggests, comparative adjectives and adverbs are used to compare an attribute between two people or things. Superlative adjectives and adverbs, on the other hand, identify someone or something with the highest (or lowest) degree of a certain attribute.
We inflect these modifiers by adding the suffix “-r” or “-er” to form the comparative degree, and “-st” or “-est” to form the superlative degree. Collectively, these are known as the degrees of comparison. For example:
Degrees of Comparison - Adjectives
Degrees of Comparison - Adverbs
“My cat has sharp claws.”
“I like to drive fast.”
“His cat has sharper claws than mine.”
“My sister drives faster than me.”
“Their cat has the sharpest claws of them all.”
“My dad drives the fastest in our family.”
For some modifiers, we simply add the words more/less or most/least rather than changing the adjective or adverb itself.
To learn the specific rules that govern the declension of adjectives and adverbs, go to the Degrees of Comparison sections for Adjectives or Adverbs.

Regular and irregular inflection

Inflection is usually determined by clear, consistent rules or patterns. This is known as regular inflection. Most of the examples we’ve looked at so far have been according to regular inflection.
However, there are also many instances of irregular inflection, in which the way the word changes is completely unique and does not follow (or seem to follow) any predetermined rules.
For instance, irregular inflection occurs with many of the plurals of nouns. Words like children or mice are irregular plural forms of child and mouse.
It also occurs with adjectives and adverbs when we decline them for the comparative and superlative forms. For example, the adjective good becomes better (comparative) and best (superlative), which are also the inflected forms of the adverb well.
Some adverbs that are formed from adjectives are also irregular—well, for instance, is the irregular adverb form of the adjective good.
Verbs are the most notorious for their irregular inflection, which is defined as having past tense and past participle forms that a) are different from one another, and b) have different spellings than the usual “-d” or “-ed” endings. For instance, the past tense of the verb sing is sang, while its past participle is sung.
Go to the section Regular and Irregular Inflection in this chapter to learn more about these tricky exceptions.

1. Which of the following is the purpose of inflection?

2. Which of the following is not something we conjugate verbs for?

3. What is the most common reason personal pronouns are inflected?

4. The subjunctive mood can be used to express which of the following?

5. Which of the following is the term for inflection that does not follow predictable rules or patterns?

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