Structural Rules of Heavy and Light Noon-e-Ta'keed

1. Heavy Noon and Light Noon Do Not Enter the Same Number of Forms

The two emphatic Noons have different ranges in the 14-form Mudhaari' grid.

Forms enteredType
14Heavy Noon
8Light Noon

Main point: Heavy Noon can enter all 14 forms, while Light Noon is excluded from 6 forms.

2. Why Light Noon Is Excluded from Six Forms

In this paradigm, Light Noon does not come after an Alif.
That excludes exactly 6 positions:
• all 4 dual forms
• both 2 feminine plural forms
So:
4 + 2 = 6
The remaining 8 positions are the forms in which Light Noon can occur.

3. A 5 + 6 + 2 + 1 Map for Heavy Noon

To understand Heavy Noon across all 14 forms, look at what comes immediately before it.

What comes before Heavy NoonFormsGroup
Fathah5five basic positions
Alif64 dual + 2 feminine plural
Dhammah2masculine plural
Kasrah1singular feminine Haadhir

Check: 5 + 6 + 2 + 1 = 14.

4. Five Forms Have Fathah Before Heavy Noon

In exactly 5 positions, the letter immediately before Heavy Noon carries Fathah.

Emphatic formPosition
لَيَفْعَلَنَّmasculine Ghaa'ib singular
لَتَفْعَلَنَّfeminine Ghaa'ib singular
لَتَفْعَلَنَّmasculine Haadhir singular
لَأَفْعَلَنَّMutakallim singular
لَنَفْعَلَنَّMutakallim plural

5. Six Forms Have an Alif Before Heavy Noon

In 6 positions, an Alif comes immediately before Heavy Noon:
• all 4 dual forms
• both 2 feminine plural forms
A dual example:
لَيَفْعَلَانِّ
In the feminine plural forms, an extra separating Alif is inserted between the subject Noon and Heavy Noon. This is called Alif-e-Faasil.
Example:
لَيَفْعَلْنَانِّ

6. Two Masculine Plural Forms: Waaw Drops

In the 2 masculine plural positions, the subject Waaw is dropped before Heavy Noon.
The preceding letter carries Dhammah as an indicator of the deleted Waaw.
Example:
يَفْعَلُونَ
becomes
لَيَفْعَلُنَّ
Recognition clue: Dhammah before Heavy Noon points to these masculine plural positions.

7. One Singular Feminine Haadhir Form: Yaa Drops

In the singular feminine Haadhir position, the subject Yaa is dropped before Heavy Noon.
The preceding letter carries Kasrah as an indicator of the deleted Yaa.
Example:
تَفْعَلِينَ
becomes
لَتَفْعَلِنَّ
Recognition clue: Kasrah before Heavy Noon points to this one position.

8. Now Look at the Vowel on Heavy Noon Itself

Do not confuse the vowel before Heavy Noon with the vowel on Heavy Noon itself.
The source gives this final rule:

Vowel on Heavy Noon itselfFormsCondition
Kasrah6an Alif comes before Heavy Noon
Fathah8all remaining positions

Examples:
لَيَفْعَلَانِّ
لَيَفْعَلَنَّ
Two maps to remember: Heavy Noon enters 14; Light Noon enters 8.