Rule 1: 1. Nisbas of place names
The nisba adjective in ـِيٌّ (feminine ـِيَّةٌ) tells where a person comes from. The final ـَاءُ or ـَةُ of a place name is dropped before it, and a few nisbas are irregular: صَنْعَاءُ gives صَنْعَانِيٌّ. Tribal and family names are often nisbas too, used with the article: رَاشِدٌ الْحِمْيَرِيُّ 'Rāshid of Ḥimyar'.
كَانَ إِلَى جَانِبِي شَيْخٌ صَنْعَانِيٌّ.
kāna ilā jānibī shaykhun ṣanʿāniyyun
Beside me was an old man from Sanaa.
Irregular nisba of صَنْعَاءُ.
سَهْلُ تِهَامَةَ سَهْلٌ تِهَامِيٌّ حَارٌّ.
sahlu tihāmata sahlun tihāmiyyun ḥārrun
The plain of Tihāma is a hot coastal plain.
تِهَامَةُ → تِهَامِيٌّ: the ة is dropped.
اِشْتَرَيْتُ عَسَلًا حَضْرَمِيًّا.
ishtaraytu ʿasalan ḥaḍramiyyan
I bought honey from Ḥaḍramawt.
حَضْرَمَوْتُ → حَضْرَمِيٌّ: compound names keep only the first part.
اَلْقَهْوَةُ الْيَمَنِيَّةُ مَشْهُورَةٌ فِي الْعَالَمِ.
al-qahwatu l-yamaniyyatu mashhūratun fi l-ʿālami
Yemeni coffee is famous throughout the world.