Rule 1: 1. Form X verbs of judgement
A large group of Form X verbs means to consider something to be …, made from an adjective: اِسْتَحْسَنَ to consider good from حَسَنٌ, اِسْتَصْعَبَ to find difficult from صَعْبٌ, اِسْتَسْهَلَ to find easy from سَهْلٌ, اِسْتَغْرَبَ to find strange from غَرِيبٌ, اِسْتَكْبَرَ to consider oneself great, be arrogant from كَبِيرٌ. The thing judged is the direct object. Beside them stand the ordinary transitive verbs of the pattern: اِسْتَقْبَلَ to receive, welcome, اِسْتَخْدَمَ to employ, use, اِسْتَمْتَعَ بِـ to enjoy.
اِسْتَغْرَبَ الْوَلَدُ النَّوْمَ عَلَى الرَّمْلِ.
istaghraba l-waladu n-nawma ʿalā r-ramli
The boy found sleeping on the sand strange.
اِسْتَصْعَبْتُ رُكُوبَ الْجِمَالِ ثُمَّ اسْتَسْهَلْتُهُ.
istaṣʿabtu rukūba l-jimāli thumma stashaltuhu
I found riding camels difficult, then I found it easy.
First person perfect: ـْتُ added to the Form X stem.
اِسْتَقْبَلَهُ خَالُهُ اسْتِقْبَالًا حَسَنًا.
istaqbalahu khāluhu stiqbālan ḥasanan
His uncle gave him a warm welcome.
The verbal noun اِسْتِقْبَالٌ repeated after its verb, with an adjective: 'he received him a good receiving'.
يَسْتَخْدِمُ الْبَدْوُ الْجِمَالَ فِي السَّفَرِ.
yastakhdimu l-badwu l-jimāla fi s-safari
The Bedouin use camels for travelling.
كُنَّا نَسْتَمْتِعُ بِاللَّيَالِي الصَّافِيَةِ تَحْتَ النُّجُومِ.
kunnā nastamtiʿu bi-l-layāli ṣ-ṣāfiyati taḥta n-nujūmi
We used to enjoy the clear nights under the stars.
كَانَ + imperfect for a habit in the past.