that when the Muaddhin fell silent following the call to Subh prayer and dawn had broken, he would pray two brief rak'ahs before getting up to pray.  

أَنَّ رَسُولَ اللَّهِ ﷺ كَانَ إِذَا سَكَتَ الْمُؤَذِّنُ مِنَ الأَذَانِ لِصَلاَةِ الصُّبْحِ وَبَدَا الصُّبْحُ صَلَّى رَكْعَتَيْنِ خَفِيفَتَيْنِ قَبْلَ أَنْ تُقَامَ الصَّلاَةُ  

Told him that when the Muaddhin fell silent, Messenger of Allah ﷺ would pray two brief rak'ahs. (Using translation from Nasāʾī 1772)   

أَنَّ رَسُولَ اللهِ ﷺ كَانَ يُصَلِّي رَكْعَتَيْنِ خَفِيفَتَيْنِ إِذَا بَدَا الْفَجْرُ  

[Machine] The mu'adhin used to pray two light optional units of prayer after the Fajr prayer, just like the Prophet ﷺ .  

كَانَ الْمُؤَذِّنُ إِذَا سَكَتَ مِنْ صَلَاةِ الصُّبْحِصَلَّى رَكْعَتَيْنِ خَفِيفَتَيْنِ تَعْنِي النَّبِيَّ ﷺ  

[Machine] The translation for the passage "أَنَّ النَّبِيَّ ﷺ كَانَ «إِذَا طَلَعَ الْفَجْرُ صَلَّى رَكْعَتَيْنِ خَفِيفَتَيْنِ»" into English is "The Prophet ﷺ used to pray two light rak'ahs when dawn broke."  

أَنَّ النَّبِيَّ ﷺ كَانَ «إِذَا طَلَعَ الْفَجْرُ صَلَّى رَكْعَتَيْنِ خَفِيفَتَيْنِ»  

[Machine] The Prophet ﷺ used to pray two light-raka'at when he saw the dawn.  

أَنَّ النَّبِيَّ ﷺ كَانَ «إِذَا رَأَى الْفَجْرَ صَلَّى رَكْعَتَيْنِ خَفِيفَتَيْنِ»  

When the Mu'adh-dhin pronounced the Adhan for Fajr prayer and the dawn became evident the Prophet ordered a two rakʿat light prayer (Sunna) before the Iqama of the compulsory (congregational) prayer. (Using translation from Bukhārī 618)   

أَنَّ رَسُولَ اللهِ ﷺ كَانَ «إِذَا سَكَتَ الْمُؤَذِّنُ لِأَذَانِ الصُّبْحِ وَبَدَا الصُّبْحُ صَلَّى رَكْعَتَيْنِ خَفِيفَتَيْنِ قَبْلَ أَنْ تُقَامَ الصَّلَاةُ»