The Prohibitive: Active and Passive Paradigms with Emphatic Nūn

1. What the prohibitive asks for

A prohibitive (nahy) requests that an action not be done. An imperative directs performance; a prohibitive requires abstention. The textbook forms it by placing lā al-nāhiyah before the imperfect, which then becomes jussive.

Word / formMeaning / explanation
اِضْرِبْstrike! (one male).
لَا تَضْرِبْdo not strike!
يَكْتُبُhe writes or will write.
لَا تَكْتُبْdo not write! (one male).

The last pair is not the same grammatical person. Formation requires the appropriate person and the jussive ending, not merely a prefixed lā.

2. Prohibitive lā versus ordinary negative lā

Lā al-nāhiyah forbids an action and makes the imperfect jussive. Ordinary negative lā (lā al-nāfiyah) negates a statement; by itself it does not impose the jussive mood.
لَا تَكْتُبْ — do not write!; the imperfect ends in sukūn.
لَا تَكْتُبُ — you do not write; the imperfect remains indicative.
Unvowelled orthography may look identical. Read the mood, intended force and context together rather than treating every occurrence of lā as a command not to act.

3. The two-step formation rule

The source’s general rule has two steps: take the appropriate active or passive imperfect, add lā at the beginning, and apply the jussive rules. The method serves all fourteen positions—third, second and first person.

Word / formMeaning / explanation
يَفْعَلُ ← لَا يَفْعَلْlet him not do it.
تَفْعَلُ ← لَا تَفْعَلْdo not do it (male).
نَفْعَلُ ← لَا نَفْعَلْlet us not do it.

The root consonants remain in place; the inserted prohibitive and the inflectional ending carry the primary grammatical change.

4. Sukūn in five regular positions

For a regular sound verb, five indicative positions normally end in ḍamma and take sukūn under the prohibitive: third-person masculine singular, third-person feminine singular, second-person masculine singular, first-person singular and first-person plural.

Word / formMeaning / explanation
يَفْعَلُ → لَا يَفْعَلْlet him not act.
تَفْعَلُ → لَا تَفْعَلْlet her not act / do not act (male), according to context.
أَفْعَلُ → لَا أَفْعَلْlet me not act.
نَفْعَلُ → لَا نَفْعَلْlet us not act.

Weak-final verbs may instead show jussive loss of a weak letter, a separate morphological case.

5. Seven endings lose the inflectional nūn

Where the imperfect has an inflectional nūn among the “five verbs” patterns, jussive formation removes that nūn. In the fourteen-person presentation, seven positions show such endings: three third-person and four second-person positions.

Word / formMeaning / explanation
يَفْعَلَانِ → لَا يَفْعَلَاlet the two men not act.
يَفْعَلُونَ → لَا يَفْعَلُواlet the men not act.
تَفْعَلِينَ → لَا تَفْعَلِيdo not act (one woman).

The dual alif, plural wāw and singular-feminine yāʾ remain; the deleted nūn was inflectional, not one of the root consonants.

6. The feminine-plural nūn remains

The feminine-plural nūn (nūn al-niswah) marks feminine plural third- and second-person forms. Unlike the nūn of indicative inflection, it is not deleted by the prohibitive; it remains part of the feminine plural form.
يَفْعَلْنَ → لَا يَفْعَلْنَ — let those women not act.
تَفْعَلْنَ → لَا تَفْعَلْنَ — do not act (women).
These forms are already built with their feminine-plural nūn rather than ordinary indicative nūn. Emphatic heavy nūn can also require a separating alif, treated later in the paradigm.

7. The six source columns

The textbook places six forms side by side: active prohibitive, passive prohibitive, active with heavy nūn, passive with heavy nūn, active with light nūn, and passive with light nūn. The active asks an agent to refrain; the passive asks that an action not be done to someone, leaving the agent unspecified.

Word / formMeaning / explanation
لَا يَفْعَلْlet him not do it.
لَا يُفْعَلْlet it not be done to him.
لَا يَفْعَلَنَّlet him certainly not do it.
لَا يَفْعَلَنْemphatic refusal with light nūn.

The prohibitive starts with lā; it is not built with the imperative or emphatic lām.

8. Third-person masculine: singular and dual

Active — Passive — Active heavy — Passive heavy — Active light — Passive light
3rd-person masculine singular
Active: لَا يَفْعَلْ
Passive: لَا يُفْعَلْ
Active with heavy nūn: لَا يَفْعَلَنَّ
Passive with heavy nūn: لَا يُفْعَلَنَّ
Active with light nūn: لَا يَفْعَلَنْ
Passive with light nūn: لَا يُفْعَلَنْ
3rd-person masculine dual
Active: لَا يَفْعَلَا
Passive: لَا يُفْعَلَا
Active with heavy nūn: لَا يَفْعَلَانِّ
Passive with heavy nūn: لَا يُفْعَلَانِّ
Both light-nūn slots are absent from the textbook paradigm.
The singular becomes jussive with sukūn; in the dual, the inflectional nūn disappears and alif remains.

9. Third-person masculine plural and feminine singular

Active — Passive — Active heavy — Passive heavy — Active light — Passive light
3rd-person masculine plural
Active: لَا يَفْعَلُوا
Passive: لَا يُفْعَلُوا
Active with heavy nūn: لَا يَفْعَلُنَّ
Passive with heavy nūn: لَا يُفْعَلُنَّ
Active with light nūn: لَا يَفْعَلُنْ
Passive with light nūn: لَا يُفْعَلُنْ
3rd-person feminine singular
Active: لَا تَفْعَلْ
Passive: لَا تُفْعَلْ
Active with heavy nūn: لَا تَفْعَلَنَّ
Passive with heavy nūn: لَا تُفْعَلَنَّ
Active with light nūn: لَا تَفْعَلَنْ
Passive with light nūn: لَا تُفْعَلَنْ
Ordinary plural prohibitives keep the wāw; emphatic forms show a contracted ending instead.

10. Third-person feminine dual and plural

Active — Passive — Active heavy — Passive heavy — Active light — Passive light
3rd-person feminine dual
Active: لَا تَفْعَلَا
Passive: لَا تُفْعَلَا
Active with heavy nūn: لَا تَفْعَلَانِّ
Passive with heavy nūn: لَا تُفْعَلَانِّ
Both light-nūn slots are absent from the textbook paradigm.
3rd-person feminine plural
Active: لَا يَفْعَلْنَ
Passive: لَا يُفْعَلْنَ
Active with heavy nūn: لَا يَفْعَلْنَانِّ
Passive with heavy nūn: لَا يُفْعَلْنَانِّ
Both light-nūn slots are absent from the textbook paradigm.
The feminine-plural nūn remains; a separating alif precedes heavy emphatic nūn.

11. Second-person masculine singular and dual

Active — Passive — Active heavy — Passive heavy — Active light — Passive light
2nd-person masculine singular
Active: لَا تَفْعَلْ
Passive: لَا تُفْعَلْ
Active with heavy nūn: لَا تَفْعَلَنَّ
Passive with heavy nūn: لَا تُفْعَلَنَّ
Active with light nūn: لَا تَفْعَلَنْ
Passive with light nūn: لَا تُفْعَلَنْ
2nd-person masculine dual
Active: لَا تَفْعَلَا
Passive: لَا تُفْعَلَا
Active with heavy nūn: لَا تَفْعَلَانِّ
Passive with heavy nūn: لَا تُفْعَلَانِّ
Both light-nūn slots are absent from the textbook paradigm.
The direct masculine prohibitive is lā tafʿal, not the positive direct imperative ifʿal.

12. Second-person masculine plural and feminine singular

Active — Passive — Active heavy — Passive heavy — Active light — Passive light
2nd-person masculine plural
Active: لَا تَفْعَلُوا
Passive: لَا تُفْعَلُوا
Active with heavy nūn: لَا تَفْعَلُنَّ
Passive with heavy nūn: لَا تُفْعَلُنَّ
Active with light nūn: لَا تَفْعَلُنْ
Passive with light nūn: لَا تُفْعَلُنْ
2nd-person feminine singular
Active: لَا تَفْعَلِي
Passive: لَا تُفْعَلِي
Active with heavy nūn: لَا تَفْعَلِنَّ
Passive with heavy nūn: لَا تُفْعَلِنَّ
Active with light nūn: لَا تَفْعَلِنْ
Passive with light nūn: لَا تُفْعَلِنْ
Feminine singular normally has final yāʾ; the emphatic ending keeps the feminine distinction through kasrah.

13. Second-person feminine dual and plural

Active — Passive — Active heavy — Passive heavy — Active light — Passive light
2nd-person feminine dual
Active: لَا تَفْعَلَا
Passive: لَا تُفْعَلَا
Active with heavy nūn: لَا تَفْعَلَانِّ
Passive with heavy nūn: لَا تُفْعَلَانِّ
Both light-nūn slots are absent from the textbook paradigm.
2nd-person feminine plural
Active: لَا تَفْعَلْنَ
Passive: لَا تُفْعَلْنَ
Active with heavy nūn: لَا تَفْعَلْنَانِّ
Passive with heavy nūn: لَا تُفْعَلْنَانِّ
Both light-nūn slots are absent from the textbook paradigm.
Feminine dual and plural are not the same number; the light-nūn slots are omitted for both.

14. First-person singular and plural

Active — Passive — Active heavy — Passive heavy — Active light — Passive light
1st-person singular
Active: لَا أَفْعَلْ
Passive: لَا أُفْعَلْ
Active with heavy nūn: لَا أَفْعَلَنَّ
Passive with heavy nūn: لَا أُفْعَلَنَّ
Active with light nūn: لَا أَفْعَلَنْ
Passive with light nūn: لَا أُفْعَلَنْ
1st-person plural
Active: لَا نَفْعَلْ
Passive: لَا نُفْعَلْ
Active with heavy nūn: لَا نَفْعَلَنَّ
Passive with heavy nūn: لَا نُفْعَلَنَّ
Active with light nūn: لَا نَفْعَلَنْ
Passive with light nūn: لَا نُفْعَلَنْ
First-person a- and na- identify number; active/passive initial vowels still distinguish voice.

15. Heavy emphatic nūn strengthens prohibition

The heavy emphatic nūn «نَّ» increases the force of a prohibition. An ordinary prohibitive asks that the act not happen; the emphatic form puts special stress on that restriction. The textbook provides its heavy-nūn forms for all fourteen persons.

Word / formMeaning / explanation
لَا تَفْعَلْdo not do it.
لَا تَفْعَلَنَّdo not do it at all!
لَا يَفْعَلْlet him not do it.
لَا يَفْعَلَنَّhe must not do it.

The heavy nūn is a grammatical emphasis marker, not a permanent consonant of the root, and the preceding ending may change with person and number.

16. Light emphatic nūn and missing positions

The light emphatic nūn «نْ» also adds emphasis to prohibition but is not doubled. The source displays light-nūn forms in eight of the fourteen positions for each voice, leaving six positions blank.

Word / formMeaning / explanation
لَا تَفْعَلَنْdo not do it, emphatically.
لَا يَفْعَلَنْlet him emphatically not do it.
لَا نَفْعَلَنْlet us certainly not do it.

Four dual positions and the two feminine-plural positions have no light-nūn entries in this source paradigm. Filling them by mechanical analogy would misrepresent the table.

17. How masculine-plural endings change

Masculine-plural imperfects contain wāw al-jamāʿah. In ordinary prohibitives the indicative nūn falls but the wāw remains; with heavy or light emphatic nūn the ending contracts. Therefore emphasis is not made by simply appending nūn to an unchanged imperfect.

Word / formMeaning / explanation
تَفْعَلُونَ → لَا تَفْعَلُواdo not act (men).
لَا تَفْعَلُنَّdo not act at all (men; heavy nūn).
لَا تَفْعَلُنْcorresponding light-nūn form.

The plural meaning remains, even though the visible ending has undergone a morphological adjustment.

18. Feminine singular prohibitives

In the second-person feminine singular imperfect, yāʾ of address is followed by an inflectional nūn. Ordinary jussive prohibition deletes that nūn but retains yāʾ. With emphatic nūn the contracted form uses kasrah to preserve the feminine address distinction.

Word / formMeaning / explanation
تَفْعَلِينَ → لَا تَفْعَلِيdo not do it (one woman).
لَا تَفْعَلِنَّemphatic feminine singular with heavy nūn.
لَا تَفْعَلِنْcorresponding light-nūn form.

All three address one woman; confusing them with «لَا تَفْعَلْ» would change the indicated gender.

19. The separating alif with feminine plural

Feminine-plural verbs already end in nūn al-niswah. When heavy emphatic nūn follows, a separating alif intervenes between the two nūns. This preserves the feminine-plural marker while distinguishing the emphatic suffix.

Word / formMeaning / explanation
لَا تَفْعَلْنَdo not act (women).
لَا تَفْعَلْنَانِّdo not act at all (women).
لَا يَفْعَلْنَانِّlet those women definitely not act.

The textbook gives no light-nūn form here. The alif separates two nūns with different grammatical roles.

20. Jussive patterns in weak-final verbs

Not every jussive verb ends in a newly added sukūn. With a weak-final verb (nāqiṣ), jussive formation can remove the final weak letter. Identify the correct imperfect stem and weak root before applying the prohibition rule.

Word / formMeaning / explanation
يَدْعُو → لَا يَدْعُlet him not call.
يَرْمِي → لَا يَرْمِlet him not throw.
يَسْعَى → لَا يَسْعَlet him not strive.

Deletion of a weak final letter is a different jussive marker from deletion of an inflectional nūn. These examples extend the basic source rule to weak-final verbs.

21. Comparing lā, lam and lan

Negative particles can differ in force, time reference and effect on the imperfect. Prohibitive lā forbids and produces the jussive; lam negates a past event and produces the jussive; lan negates a future event and produces the subjunctive.

Word / formMeaning / explanation
لَا تَضْرِبْdo not strike.
لَمْ تَضْرِبْyou did not strike.
لَنْ تَضْرِبَyou will not strike.

All three are negative in some sense, but their grammatical operation and sentence function differ. This distinction also appears in the source exercises.

22. Positive direction versus negative prohibition

Both lām al-amr and prohibitive lā can govern a jussive imperfect, yet their meanings oppose each other. The first demands performance; the second demands abstention. A change in the initial particle may reverse the instruction.

Word / formMeaning / explanation
لِيَكْتُبْlet him write.
لَا يَكْتُبْlet him not write.
لِتَكْتُبْlet you write (lām al-amr construction).
لَا تَكْتُبْdo not write.

The final sukūn may be shared; it is the initial particle and intended meaning that decide whether the clause is affirmative or prohibitive.

23. Applying the textbook’s model to new roots

The source exercises ask for complete prohibitive conjugations of forms such as لَا يَجْتَنِبْ، لَا يَتْرُكْ، لَا يَمْنَعْ. Keep the appropriate imperfect stem and verb form, then apply the jussive rule to each person.

Word / formMeaning / explanation
يَجْتَنِبُ → لَا يَجْتَنِبْhe avoids → let him not avoid.
تَتْرُكِينَ → لَا تَتْرُكِيyou (woman) leave → do not leave.
تَمْنَعُونَ → لَا تَمْنَعُواyou (men) prevent → do not prevent.

Ijtināb belongs to a derived verb form with a different internal pattern, but the prohibitive jussive operation still applies.

24. Meaning and person in translation

Translation of a prohibitive must preserve four things: negation, person, number and gender. A generic “do not” is inadequate when the source differentiates dual, plural and feminine forms.

Word / formMeaning / explanation
لَا تَسْمَعَاdo not listen (two people).
لَا تَسْمَعُواdo not listen (men, plural).
لَا تَسْمَعِيdo not listen (one woman).
لَا يَسْمَعْنَlet those women not listen.

For Urdu-to-Arabic exercises, first identify the grammatical subject or passive patient, then form the correct person of the prohibitive.

25. Integrated recognition and production

The core prohibitive structure is lā al-nāhiyah + jussive imperfect. In sound verbs, five person positions take sukūn, seven lose the inflectional nūn, and two feminine-plural positions retain nūn al-niswah. The internal vowel pattern distinguishes active from passive.

Word / formMeaning / explanation
لَا تَكْتُبْactive, second masculine singular, ordinary prohibition.
لَا تُكْتَبْpassive, second masculine singular, ordinary prohibition.
لَا تَكْتُبَنَّactive, same person, heavy nūn.
لَا تَكْتُبَنْactive, same person, light nūn.

Correct recognition uses the complete form, its vowels, person and final marker—not lā alone.