Rule 1: 1. مَرَّ بِـ, to pass by
To pass by something is مَرَّ بِـ: the thing passed is introduced by بِ, never by a direct object. مَرَّ is a doubled verb, its second and third root letters are the same ر, written once with shadda. Before the endings that begin with a consonant the two ر separate again: مَرَرْتُ I passed, مَرَرْنَا we passed. The imperfect is يَمُرُّ.
مَرَّ التَّاجِرُ بِالْبَيْتِ.
marra-t-tājiru bi-l-bayti
The merchant passed by the house.
مَرَّتْ زَيْنَبُ بِي فِي السُّوقِ.
marrat zaynabu bī fi-s-sūqi
Zaynab passed by me in the market.
بِ with the suffix of 'me'.
مَرَرْنَا بِمَطَاعِمَ كَثِيرَةٍ.
mararnā bi-maṭāʿima kathīratin
We passed by many restaurants.
The doubling opens before ـنَا; the diptote shows fatḥa after بِ.
كُلَّ يَوْمٍ يَمُرُّ الْأَوْلَادُ بِقَفَصِ الْبَبَّغَاءِ.
kulla yawmin yamurru-l-awlādu bi-qafaṣi-l-babbaghāʾi
Every day the boys pass by the parrot's cage.