Līn occurs when a quiescent wāw or yāʾ follows fatḥah rather than the matching vowel associated with madd. This produces a diphthong-like sound rather than the long-vowel combination.
قَوْلٌ — sākin wāw following fatḥah: wāw of līn.
بَيْعٌ — sākin yāʾ following fatḥah: yāʾ of līn.
In يَقُولُ, the wāw follows ḍammah and forms madd; in قَوْلٌ, it follows fatḥah and forms līn. The letter is the same, but the preceding vowel changes the classification.
Opening interactive controls...
Letters of Līn
The Seven Morphological Classes: Sound, Hamzated, Weak and Doubled
Līn occurs when a quiescent wāw or yāʾ follows fatḥah rather than the matching vowel associated with madd. This produces a diphthong-like sound rather than the long-vowel combination.
قَوْلٌ — sākin wāw following fatḥah: wāw of līn.
بَيْعٌ — sākin yāʾ following fatḥah: yāʾ of līn.
In يَقُولُ, the wāw follows ḍammah and forms madd; in قَوْلٌ, it follows fatḥah and forms līn. The letter is the same, but the preceding vowel changes the classification.