Trilateral Bare Irregular - Bab 1: Hasiba Yahsibu

1. What Does Shadh Mean Here?

After the regular doors, this course now introduces the Shadh doors: patterns that occur less frequently.
The source groups the triliteral bare Shadh section into 3 doors.
The first of these is حَسِبَ يَحْسِبُ.

2. Bab 1: Hasiba Yahsibu

The first Shadh door is حَسِبَ يَحْسِبُ.
Its basic signature is that the middle root letter has Kasrah in both past and Mudhaari'.
The verbal nouns given here are الحِسْبُ and الحِسْبَانُ, with the sense of reckoning, considering, or supposing.

3. First Half of the Sarf-e-Sagheer

Read the opening in two connected blocks.
1. Active: حَسِبَ يَحْسِبُ حِسْبًا وَحِسْبَانًا فَهُوَ حَاسِبٌ.
2. Passive: حُسِبَ يُحْسَبُ حِسْبًا فَهُوَ مَحْسُوْبٌ.
So the first half gives the active and passive verbs together with Ism Fa'il and Ism Maf'ool.

4. Command and Prohibition

The next two forms are straightforward.

FormCategory
اِحْسِبْImperative
لَا تَحْسِبْProhibitive

Keep them together as a pair when revising the Bab.

5. Dharf and Instrument Forms

The derived-noun block then moves to Dharf and instrument forms.

FormCategory
مَحْسِبٌIsm Dharf
مِحْسِبٌIsm Aalah — Sughraa
مِحْسِبَةٌIsm Aalah — Wustaa
مِحْسَابٌIsm Aalah — Kubraa

The instrument plurals shown are مَحَاسِبُ and مَحَاسِيْبُ.

6. Ism Tafdheel Forms

The final block contains the comparative forms.

FeminineMasculineNumber / type
حُسْبَىٰأَحْسَبُSingular
حُسْبَيَانِأَحْسَبَانِDual
حُسْبَيَاتٌ / حُسَبٌأَحْسَبُوْنَ / أَحَاسِبُPlural forms

7. A Simple Map of the Level

Remember these points:
1. The Shadh section contains 3 doors in this source.
2. The first is حَسِبَ يَحْسِبُ.
3. Its verbal nouns here are الحِسْبُ and الحِسْبَانُ.
4. Its Sarf-e-Sagheer follows the familiar active → passive → command/prohibition → Dharf/instrument → comparative sequence.
5. Important noun forms include حَاسِبٌ, مَحْسُوْبٌ, and مَحْسِبٌ.