Pairs of two rakahs are the normal sunnah form, while different combinations of rakahs under one salam raise distinct questions of validity and counting.
Likewise, the rest after every four is recommended; shortening a rest is not the same legal issue as combining four rakahs into a single prayer. One concerns organization and the other concerns prayer structure and sitting.
Opening interactive controls...
Qiyam Ramadan: Tarawih, Qur’an Recitation, and Witr Congregation
Pairs of two rakahs are the normal sunnah form, while different combinations of rakahs under one salam raise distinct questions of validity and counting.
Likewise, the rest after every four is recommended; shortening a rest is not the same legal issue as combining four rakahs into a single prayer. One concerns organization and the other concerns prayer structure and sitting.