The Messenger of Allah ﷺ used to observe four rak'ahs in the forenoon prayer and he sometimes observed more as Allah pleased.  

كَانَ رَسُولُ اللَّهِ ﷺ يُصَلِّي الضُّحَى أَرْبَعًا وَيَزِيدُ مَا شَاءَ اللَّهُ  

[Machine] The translation of the passage into English is: "Indeed, the Prophet ﷺ used to pray four units of the Duha prayer, and he would increase as Allah willed."  

أَنَّ النَّبِيَّ ﷺ كَانَ يُصَلِّي الضُّحَى أَرْبَعًا وَيَزِيدُ مَا شَاءَ اللهُ  

[Machine] The Prophet ﷺ used to pray four units of the Duha prayer and would increase as Allah willed.  

كَانَ النَّبِيُّ ﷺ يُصَلِّي صَلَاةَ الضُّحَى أَرْبَعَ رَكَعَاتٍ وَيَزِيدُ مَا شَاءَ اللهُ  

The Messenger of Allah ﷺ used to observe four rak'ahs in the forenoon prayer and he sometimes observed more as Allah pleased. (Using translation from Muslim 719c)   

كَانَ رَسُولُ اللهِ ﷺ «يُصَلِّي الضُّحَى أَرْبَعًا وَيَزِيدُ مَا شَاءَ اللهُ» خَالَفَهَا عُرْوَةُ