A hamzah can be an original root consonant; it must not be confused with an auxiliary hamzat al-waṣl.
Root/formRepresentative outcomePoint
أ ك لأَكَلَ / كُلْA special imperative lightening
ء م نأَأْمَنَ → آمَنَTwo hamzahs lead to substitution
س ء ليَسْأَلُLightened pronunciations may transfer a vowel
ق ر ءقَرَأَFinal root hamzah
Lightening affects pronunciation/form, not the lexical identity of the root. Do not universalize one alteration to every hamzated word; each of the book’s five rules has its conditions.