How to Say “Why Didn’t You…?” in Arabic: Using مَا مَنَعَ ... أَنْ

Imagine that your friend arrived late for work.

You know there was a bus available, so you want to ask:

“Why didn’t you take the bus?”

In Modern Standard Arabic, one useful way to ask this type of question is with the pattern:

مَا مَنَعَ ... أَنْ

What prevented … from …? / Why didn’t …?

For example:

مَا مَنَعَكَ أَنْ تَأْخُذَ الْحَافِلَةَ؟ Why didn’t you take the bus?

This lesson will show you what the expression means, how it is built, and how you can reuse it in your own everyday Arabic.

1. The Arabic "مَا مَنَعَ ... أَنْ" Expression

To ask someone why they didn't do something, Arabic speakers frequently use this pattern:

مَا مَنَعَ ... أَنْ

Transliteration:
mā manaʿa ... ʾan

Natural English meaning:
Why didn’t …?

Literal meaning:
What prevented … from …?

2. What Does “مَا مَنَعَ ... أَنْ” Mean?

Consider this sentence:

مَا مَنَعَكَ أَنْ تَشْرَبَ الْقَهْوَةَ مَعَنَا؟ Why didn’t you drink coffee with us?

Literally, the Arabic sentence asks:
What prevented you from drinking coffee with us?

The speaker is asking about the reason or obstacle that stopped the person from doing something.

Because English often expresses this idea more simply, “Why didn’t you…?” is usually a natural translation.

An Important Meaning Note

مَا مَنَعَكَ أَنْ...؟ can sound slightly more specific than a completely neutral “Why didn’t you…?”

It often means:
“What stopped you?”
or
“Was there something that prevented you?”

If you simply want to ask a neutral “Why didn’t you…?”, Arabic also has other structures.

For this lesson, however, we will focus on learning مَا مَنَعَ ... أَنْ as one useful and reusable pattern.

3. How the “مَا مَنَعَ ... أَنْ” Expression Is Built

Let's break down the sentence into easy pieces.

The Core Structure:

(Maa mana'a + attached object pronoun + 'an + present tense verb in the subjunctive state?)

• مَا (mā): What.
• مَنَعَ (manaʿa): Prevented.
• الضَّمِير (aḍ-ḍamīr) — attached object pronoun: This is who you are talking to or about (e.g., you, him, her).
• أَنْ (ʾan): To / that.
• الْفِعْل الْمُضَارِع (al-fiʿl al-muḍāriʿ) — present-tense verb: The action they didn't do.

4. The Grammar Behind the Pattern

You do not need advanced Arabic grammar to use this expression, but one rule is very important.

أَنْ Changes the Following Verb

The word:
أَنْ

is called:
حَرْفُ نَصْبٍ وَمَصْدَرٍ — a subjunctive and infinitival particle.

The verb after أَنْ is a:
فِعْلٌ مُضَارِعٌ مَنْصُوبٌ — an imperfect/present-tense verb in the subjunctive form.

For a beginner, the practical rule is:
When you use أَنْ, check whether the ending of the following present-tense verb needs to change.

For example:
تَشْرَبُ you drink

becomes:
أَنْ تَشْرَبَ to drink

Notice the final vowel:
ـُ → ـَ

Compare:
تَدْرُسُ you study
أَنْ تَدْرُسَ to study

And:
يَقْرَأُ he reads
أَنْ يَقْرَأَ to read

4a. What Happens with “You” Feminine?

Consider:
أَنْتِ تَذْهَبِينَ You go. — feminine singular

After أَنْ, the final ن disappears:
أَنْ تَذْهَبِي to go

This happens because تَذْهَبِينَ belongs to a group called:
الْأَفْعَالُ الْخَمْسَةُ — the five verb forms.

With these forms, the subjunctive after أَنْ is often shown by:
حَذْفُ النُّونِ — dropping the final nūn.

So:
تَذْهَبِينَ → أَنْ تَذْهَبِي تَحْضُرِينَ → أَنْ تَحْضُرِي تَشْرَبِينَ → أَنْ تَشْرَبِي

4b. What Happens with Plural “You”?

The same principle applies:
تَنَامُونَ you sleep

becomes:
أَنْ تَنَامُوا to sleep

And:
تَسْأَلُونَ you ask
becomes:
أَنْ تََسْأَلُوا to ask

Again, the ن disappears.

5. The Reusable Sentence Pattern

The basic formula is:

For example:
مَا مَنَعَكَ أَنْ تَدْرُسَ؟ Why didn’t you study?

You can change the attached pronoun depending on the person you are asking or talking about.

Masculine singular “you”
مَا مَنَعَكَ أَنْ ...؟ Why didn’t you…?

Feminine singular “you”
مَا مَنَعَكِ أَنْ ...؟ Why didn’t you…?

“He”
مَا مَنَعَهُ أَنْ ...؟ Why didn’t he…?

“She”
مَا مَنَعَهَا أَنْ ...؟ Why didn’t she…?

Plural “you”
مَا مَنَعَكُمْ أَنْ ...؟ Why didn’t you all…?

“They”
مَا مَنَعَهُمْ أَنْ ...؟ Why didn’t they…?

The attached pronoun functions as:
مَفْعُولٌ بِهِ — a direct object.

You do not need to memorize that grammatical term immediately. For practical use, simply notice that the pronoun is attached directly to مَنَعَ.

6. Simple Sentence Examples (A1 level sentences)

Start by noticing the repeated pattern.

Example 1
مَا مَنَعَكَ أَنْ تَشْرَبَ الْقَهْوَةَ مَعَنَا؟ Why didn’t you drink coffee with us?

Notice:
مَا مَنَعَكَ أَنْ + تَشْرَبَ The question is addressed to one male person.

Example 2
مَا مَنَعَكِ أَنْ تَذْهَبِي إِلَى النَّادِي؟ Why didn’t you go to the club?

The question is addressed to one female person.
The normal verb is:
تَذْهَبِينَ After أَنْ:
أَنْ تَذْهَبِي

Example 3
مَا مَنَعَكُمْ أَنْ تَنَامُوا مُبَكِّرًا؟ Why didn’t you go to bed early?

Here, the speaker is talking to more than one person.
تَنَامُونَ → أَنْ تَنَامُوا

Example 4
مَا مَنَعَكَ أَنْ تَدْرُسَ اللُّغَةَ الْعَرَبِيَّةَ الْيَوْمَ؟ Why didn’t you study Arabic today?

This is a useful sentence for talking about study routines.

Example 5
مَا مَنَعَهُ أَنْ يَقْرَأَ هَذَا الْكِتَابَ؟ Why didn’t he read this book?

The normal form:
يَقْرَأُ After أَنْ:
أَنْ يَقْرَأَ

7. More Sentence Examples (A2 level sentences)

Now the same pattern can be used with slightly more varied vocabulary.

Example 6
مَا مَنَعَهُ أَنْ يَتَنَاوَلَ الْفَطُورَ صَبَاحًا؟ Why didn’t he have breakfast in the morning?

Useful expression:
يَتَنَاوَلُ الْفَطُورَ to have breakfast
After أَنْ:
أَنْ يَتَنَاوَلَ الْفَطُورَ

Example 7
مَا مَنَعَهَا أَنْ تَشْتَرِيَ التَّذْكِرَةَ أَمْسِ؟ Why didn’t she buy the ticket yesterday?

The normal form is:
تَشْتَرِي After أَنْ:
أَنْ تَشْتَرِيَ

Notice the final fatḥah:
ـيَ This is different from feminine “you”:
أَنْتِ تَشْتَرِينَ → أَنْ تَشْتَرِي

Compare:
مَا مَنَعَهَا أَنْ تَشْتَرِيَ التَّذْكِرَةَ؟ Why didn’t she buy the ticket?
but:
مَا مَنَعَكِ أَنْ تَشْتَرِي التَّذْكِرَةَ؟ Why didn’t you buy the ticket? — speaking to a woman

The two forms look very similar, but their grammar is different.

Example 8
مَا مَنَعَكِ أَنْ تَحْضُرِي الِاجْتِمَاعَ؟ Why didn’t you attend the meeting?

This is useful in school and work situations.
The normal form:
تَحْضُرِينَ After أَنْ:
أَنْ تَحْضُرِي

Example 9
مَا مَنَعَكُمْ أَنْ تَسْأَلُوا الْمُدَرِّسَ؟ Why didn’t you ask the teacher?

The normal plural form is:
تَسْأَلُونَ After أَنْ:
أَنْ تَسْأَلُوا

Example 10
مَا مَنَعَهَا أَنْ تَكْتُبَ الْوَاجِبَ؟ Why didn’t she write the homework assignment?

The verb:
تَكْتُبُ becomes:
أَنْ تَكْتُبَ

8. Common Mistakes English Speakers Should Avoid

Mistake 1: Translating English Word for Word
English speakers may try to build “Why didn’t you…?” one English word at a time.
That is not the best way to learn this Arabic expression.
Instead, memorize the complete frame:
مَا مَنَعَكَ أَنْ ...؟ Think of it as one reusable pattern.
Then change only the verb and the other information.

For example:
مَا مَنَعَكَ أَنْ تَدْرُسَ؟ Why didn’t you study?
مَا مَنَعَكَ أَنْ تَأْكُلَ؟ Why didn’t you eat?
مَا مَنَعَكَ أَنْ تَذْهَبَ؟ Why didn’t you go?

Mistake 2: Forgetting the Verb Change After أَنْ

Incorrect:
مَا مَنَعَكَ أَنْ تَشْرَبُ الْقَهْوَةَ؟

Correct:
مَا مَنَعَكَ أَنْ تَشْرَبَ الْقَهْوَةَ؟ Why didn’t you drink the coffee?

After أَنْ, the verb must use the appropriate subjunctive form.

Mistake 3: Keeping the Final ن with Feminine or Plural Forms

Incorrect:
مَا مَنَعَكِ أَنْ تَذْهَبِينَ؟

Correct:
مَا مَنَعَكِ أَنْ تَذْهَبِي؟ Why didn’t you go?

Incorrect:
مَا مَنَعَكُمْ أَنْ تَنَامُونَ؟

Correct:
مَا مَنَعَكُمْ أَنْ تَنَامُوا؟ Why didn’t you sleep?

9. Examples of using مَا مَنَعَ ... أَنْ in real-life dialogues

Dialogue 1: Transportation
A: مَا مَنَعَكَ أَنْ تَأْخُذَ الْحَافِلَةَ؟
Why didn’t you take the bus?
B: كَانَتِ الْحَافِلَةُ مُتَأَخِّرَةً.
The bus was late.

Dialogue 2: At Work
A: مَا مَنَعَكِ أَنْ تَحْضُرِي الِاجْتِمَاعَ؟
Why didn’t you attend the meeting?
B: كُنْتُ مَرِيضَةً.
I was sick.

Dialogue 3: Friends hanging out
A: مَا مَنَعَكُمْ أَنْ تَسْأَلُوا الْمُدَرِّسَ؟
Why didn’t you ask the teacher?
B: نَسِينَا بَعْدَ الدَّرْسِ.
We forgot after the lesson.

Dialogue 4: Studying
A: مَا مَنَعَكَ أَنْ تَدْرُسَ الْيَوْمَ؟
Why didn’t you study today?
B: كَانَ عِنْدِي عَمَلٌ كَثِيرٌ.
I had a lot of work.

11. Use the Pattern in Your Own Sentences

Now move from practice to personal communication.

Complete these sentences with information from your own life.

About food
مَا مَنَعَكَ أَنْ تَأْكُلَ ______؟ Why didn’t you eat ______?

Possible vocabulary:
الْفَطُورَ breakfast
الْغَدَاءَ lunch

About transportation
مَا مَنَعَكَ أَنْ تَأْخُذَ ______؟ Why didn’t you take ______?

Possible vocabulary:
الْحَافِلَةَ the bus

About studying
مَا مَنَعَكَ أَنْ تَدْرُسَ ______؟ Why didn’t you study ______?

Possible vocabulary:
اللُّغَةَ الْعَرَبِيَّةَ Arabic

About communication
مَا مَنَعَكَ أَنْ تُرْسِلَ ______؟ Why didn’t you send ______?

Possible vocabulary:
الْبَرِيدَ الْإِلِكْتُرُونِيَّ the email

Personal Challenge
Try creating three sentences:

1. One sentence about work or school.
2. One sentence about food or shopping.
3. One sentence about transportation or travel.

Use the frame:
مَا مَنَعَ ______ أَنْ ______؟

Your goal is not to memorize every example.
Your goal is to learn the pattern so that you can create new sentences.

12. Quick Review

1. What does the expression mean?
مَا مَنَعَ ... أَنْ What prevented … from …? / Why didn’t …?

2. What is the basic pattern?
مَا مَنَعَ + attached pronoun + أَنْ + present-tense verb in the subjunctive form

Example:
مَا مَنَعَكَ أَنْ تَدْرُسَ؟ Why didn’t you study?

3. What happens after أَنْ?
The following:
فِعْلٌ مُضَارِعٌ — imperfect/present-tense verb
becomes:
مَنْصُوبًا — subjunctive.

For many regular verbs:
تَدْرُسُ → أَنْ تَدْرُسَ

For feminine singular and plural forms belonging to:
الْأَفْعَالُ الْخَمْسَةُ — the five verb forms,
the final ن is removed:
تَذْهَبِينَ → أَنْ تَذْهَبِي تَنَامُونَ → أَنْ تَنَامُوا

Conclusion

The expression:
مَا مَنَعَ ... أَنْ gives you a useful way to ask why someone did not do something.

Instead of memorizing many separate questions, learn the reusable frame:
مَا مَنَعَ + person + أَنْ + action؟

Then change the person and action.

For example:
مَا مَنَعَكَ أَنْ تَدْرُسَ؟ Why didn’t you study?
مَا مَنَعَكِ أَنْ تَذْهَبِي؟ Why didn’t you go?
مَا مَنَعَهُ أَنْ يَقْرَأَ؟ Why didn’t he read?
مَا مَنَعَكُمْ أَنْ تَسْأَلُوا؟ Why didn’t you ask?

Vocabulary List

Nouns

• الْفَطُورُ: breakfast
• الْقَهْوَةُ: coffee
• الْحَافِلَةُ: bus
• السُّوقُ: market
• الْمَتْجَرُ: store
• التَّذْكِرَةُ: ticket
• النَّادِي: club
• الِاجْتِمَاعُ: meeting
• الْمُدَرِّسُ: teacher
• الْوَاجِبُ: homework / assignment
• الْبَرِيدُ الْإِلِكْتُرُونِيُّ: email
• مِظَلَّةٌ: umbrella

Verbs

• مَنَعَ - يَمْنَعُ: to prevent / stop
• شَرِبَ - يَشْرَبُ: to drink
• ذَهَبَ - يَذْهَبُ: to go
• أَكَلَ - يَأْكُلُ: to eat
• أَخَذَ - يَأْخُذُ: to take
• دَرَسَ - يَدْرُسُ: to study
• قَرَأَ - يَقْرَأُ: to read
• اِشْتَرَى - يَشْتَرِي: to buy
• حَضَرَ - يَحْضُرُ: to attend
• سَأَلَ - يَسْأَلُ: to ask
• كَتَبَ - يَكْتُبُ: to write
• نَامَ - يَنَامُ: to sleep
• أَرْسَلَ - يُرْسِلُ: to send
• اِنْتَظَرَ - يَنْتَظِرُ: to wait