[Machine] The Messenger of Allahﷺ said that the night prayer should be performed in pairs. And when the dawn approaches, complete your night prayer with an odd-numbered unit of prayer, which will serve as the Witr prayer for you. Abdullah used to perform the Witr prayer with only one unit.
قَالَ رَسُولُ اللهِ ﷺ صَلَاةُ اللَّيْلِ مَثْنَى مَثْنَى فَإِذَا خِفْتَ الْفَجْرَ فَأَوْتِرْ بِرَكْعَةٍ تُوتِرُ لَكَ صَلَاتَكَ قَالَ وَكَانَ عَبْدُ اللهِ يُوتِرُ بِوَاحِدَةٍ
A man stood up and said. Messenger of Allah, how is the night prayer? The Messenger of Allah ﷺ said: The night prayer consists of pair, but if you apprehend the rise of dawn, make it odd number by observing one rak'ah.
يَا رَسُولَ اللَّهِ كَيْفَ صَلاَةُ اللَّيْلِ قَالَ رَسُولُ اللَّهِ ﷺ صَلاَةُ اللَّيْلِ مَثْنَى مَثْنَى فَإِذَا خِفْتَ الصُّبْحَ فَأَوْتِرْ بِوَاحِدَةٍ
"A man stood up and said: 'O Messenger of Allah ﷺ, how are the prayers at night to be done?' The Messenger of Allah ﷺ said: 'Prayers at night are (offered) two by two, then if you fear that dawn will come, pray witr with one.'"
يَا رَسُولَ اللَّهِ كَيْفَ صَلاَةُ اللَّيْلِ فَقَالَ رَسُولُ اللَّهِ ﷺ صَلاَةُ اللَّيْلِ مَثْنَى مَثْنَى فَإِذَا خِفْتَ الصُّبْحَ فَأَوْتِرْ بِوَاحِدَةٍ
A man said, "O Messenger of Allah ﷺ! How is the prayer of the night?" He said, "Two rakʿat followed by two rakʿat and so on, and when you apprehend the approaching dawn, offer one rakʿa as witr." (Using translation from Bukhārī 1137)
قَالَ النَّبِيُّ ﷺ صَلَاةُ اللَّيْلِ مَثْنَى مَثْنَى فَإِذَا خِفْتَ الصُّبْحَ فَأَوْتِرْ بِوَاحِدَةٍ
The Prophet ﷺ said: "Prayers at night are two by two, then if you fear that dawn will come, pray witr with one rak'ah." (Using translation from Nasāʾī 1668)
أَنَّ النَّبِيَّ ﷺ قَالَ صَلَاةُ اللَّيْلِ مَثْنَى مَثْنَى فَإِذَا خَشِيتَ الْفَجْرَ فَأَوْتِرْ بِوَاحِدَةٍ
A man said, "O Messenger of Allah ﷺ! How is the prayer of the night?" He said, "Two rakʿat followed by two rakʿat and so on, and when you apprehend the approaching dawn, offer one rakʿa as witr." (Using translation from Bukhārī 1137)
عَنِ النَّبِيِّ ﷺ قَالَ «صَلَاةُ اللَّيْلِ مَثْنَى مَثْنَى فَإِذَا خِفْتَ الصُّبْحَ فَأَوْتِرْ بِرَكْعَةٍ»
A man said, "O Messenger of Allah ﷺ! How is the prayer of the night?" He said, "Two rakʿat followed by two rakʿat and so on, and when you apprehend the approaching dawn, offer one rakʿa as witr." (Using translation from Bukhārī 1137)
عَنِ النَّبِيِّ ﷺ قَالَ «صَلَاةُ اللَّيْلِ مَثْنَى مَثْنَى فَإِذَا خِفْتَ الصُّبْحَ فَأَوْتِرْ بِرَكْعَةٍ»
"صَلاة اللَّيلِ مَثْنَى مَثْنَى، فَإِذَا خِفْتَ الصُّبْحَ فَأَوْتِر بِوَاحِدَةٍ؛ فَإِنَّ الله وترٌ يُحِبُّ الْوتْرَ".