What are "Might" and "May" in English Grammar?
Might and may are two closely related modal verbs used to express possibility and uncertainty in the present or future. We use them when we believe something could happen or is true, but we are not 100% certain. They signify a "chance" of something occurring without guaranteeing it.
Additionally, may is traditionally used in very formal contexts to ask for, grant, or refuse permission.
As modal verbs, might and may do not change form depending on the subject (there is no -s added for he/she/it) and they are always followed by the bare infinitive of the main verb (without "to").
"Might" and "May" Structure and Formula
Constructing sentences with might and may follows standard modal verb rules. Notice that negative contractions (mightn't, mayn't) are extremely rare or archaic in modern spoken English and should be avoided in favor of the full negative forms.
Standard Formula:
- Positive: Subject + might / may + base verb + Object
- Negative: Subject + might not / may not + base verb + Object
- Question (May only): May + Subject + base verb + Object?
Pedagogical shorthand:
- (+) S + might/may + V(bare) + O
- (-) S + might not / may not + V(bare) + O
- (?) May + S + V(bare) + O?
How to Form "Might" and "May": Positive, Negative, and Questions
Positive (Affirmative) Sentences
| Subject (S) | Modal | Main Verb (V_bare) | Object/Complement |
|---|---|---|---|
| I / You / They | might / may | come | to the party later. |
| He / She / It | might / may | rain | this afternoon. |
Example: She might arrive before noon if traffic is light.
Negative Sentences
To say it is possible that something will not happen, use might not or may not.
| Subject (S) | Modal with Not | Main Verb (V_bare) | Object/Complement |
|---|---|---|---|
| They | might not / may not | agree | with our proposal. |
| He | might not / may not | be | at home right now. |
Example: You might not need to wear a heavy jacket today.
Questions (Primarily "May")
Questions using might ("Might it rain?") are very formal and rare. We generally only invert the subject and modal when using May to ask for permission.
| Modal | Subject (S) | Main Verb (V_bare) | Object/Complement |
|---|---|---|---|
| May | I | use | your telephone? |
| May | we | leave | the classroom now? |
When to Use "Might" and "May" in English
While interchangeable in many situations, there are specific contexts dictating which one is preferred.
1. Present or Future Possibility
Use might or may when asserting that something is a distinct possibility but not a certainty. Today, they are largely interchangeable, although some grammarians argue may implies a slightly stronger possibility than might.
- It might rain later, so bring an umbrella.
- She may accept the job offer in London.
2. Formal Permission
Use may (never might) in highly formal or polite situations to ask for or grant permission.
- May I see your passport, please? (Formal polite request).
- You may now open your examination booklets. (Formal permission granted).
- You may not leave until the bell rings. (Formal permission denied).
3. Tentative Suggestions
Use might to introduce a soft, non-imposing suggestion.
- You might want to review the instructions before starting.
- It might be a good idea to call ahead to reserve a table.
4. Past Possibility (Might have / May have)
To speculate about an uncertain event that already occurred in the past, use might have or may have followed by a past participle (V3/ed).
Formula: S + might/may have + V(ed/V3) + O
- He might have forgotten we had a meeting. (It is possible that he forgot).
- They may have left already.
Common Signal Words for "Might" and "May"
Context clues that indicate uncertainty or speculation often trigger the use of might or may:
- Possibility markers: perhaps, maybe, possibly (e.g., Maybe he might call tonight.)
- Expressions of doubt: I'm not sure, I think, I believe, it's possible
- Conditions: If we rush, we might...
How to Tell the Difference Between "Might", "May", and Similar Grammar Topics
"Might" vs. "May"
- May is often considered slightly more probable (e.g., a 50% chance). It is also strictly used for formal permission.
- Might is considered slightly less probable (e.g., a 30% chance) and is used for softer suggestions. However, in modern everyday conversation, this difference in probability is often ignored.
"Might Not" vs. "Must Not"
This is a critical distinction that causes confusion.
- Might not means possibility of absence: It is possible that she will not go.
- Must not means strict prohibition: She is forbidden to go.
"Might" vs. "Could"
Both express possibility.
- Might often refers to the likelihood of an event occurring (It might rain).
- Could sometimes relates more to theoretical ability or options (We could go to the park, or we could go to the movies).
Common Mistakes with "Might" and "May"
- ❌ Mistake: Adding an "-s" to the modal.
- Incorrect: She mights go to the store.
- Correct: She might go to the store.
- ❌ Mistake: Using "to" after the modal.
- Incorrect: They may to leave early.
- Correct: They may leave early.
- ❌ Mistake: Using a base verb instead of a past participle after might have.
- Incorrect: He might have go.
- Correct: He might have gone.
- ❌ Mistake: Using question forms with might for simple possibility.
- Incorrect: Might it snow today? (Archaic/Awkward).
- Correct: Do you think it will snow today? / Could it snow today?
Real-life Examples of "Might" and "May" Usage
- (Possibility): It might snow tomorrow, so make sure to dress warmly.
- (Negative Possibility): She may not be in the office; try calling her mobile instead.
- (Uncertain Plan): I might go to the cinema tonight, but I haven't decided yet.
- (Permission Request): May I open the window? It's feeling a little warm in here.
- (Permission Granted): You may take one of those brochures if you like.
- (Suggestion): You might want to read the user manual first.
- (Speculation): She may be running late because the traffic is terrible today.
- (Past Possibility): I might have left my keys at the restaurant last night.
- (Past Possibility): The package may have arrived while we were out.
- (Negative Past Possibility): They might not have received the email notification.
Summary & Cheatsheet for "Might" and "May"
| Meaning | Modal | Structure | Example |
|---|---|---|---|
| Present/Future Possibility | might / may | S + might/may + V(bare) | It might rain later. |
| Negative Possibility | might not / may not | S + might not/may not + V(bare) | He may not agree. |
| Polite Permission | may | May + S + V(bare)? | May I come in? |
| Tentative Suggestion | might | S + might + V(bare) | You might want to check again. |
| Past Possibility | might have / may have | S + might/may have + V(ed/V3) | She might have forgotten. |
Frequently Asked Questions
Is it wrong to use "can" to ask for permission instead of "may"?
No, it is not wrong in modern English. While strictly traditional grammarians argue that "can" refers to ability (Can I physically do it?) and "may" refers to permission (Am I allowed?), in reality, native speakers use "Can I..." for permission all the time in everyday situations. "May I..." is simply reserved for very formal or highly polite situations.
Can I say "mightn't" or "mayn't"?
While technically grammatically correct, these contractions are practically obsolete in modern American English and look extremely outdated. Even in British English, they are relatively rare. It is much safer and more natural to say "might not" and "may not".
Are "might" and "may" past tense and present tense?
Historically, might was the past morphological form of may. However, today they are both used to talk about the present and future. When you want to definitively push the uncertainty into the past, you must append "have + past participle" (e.g., He might have been there).