The discussion identifies eight letter headings that require particular attention: ل، ر، م، ن، ا، و، ي، ء. Special attention is needed when mim and nun are unvowelled or doubled; the rules of tanwin are related to unvowelled nun. The behavior of waw and ya depends on their stillness and the preceding vowel.
An inherent quality and a context-dependent treatment must not be confused. Takrir is an inherent quality of ra, while making ra heavy (mufakhkham) or light (muraqqaq) depends on the relevant reading condition.
This level studies the contextual treatment of lam and ra. The more detailed rules for mim, nun and the lengthening letters form separate units.