question #3 Sahih Muslim 705f, Book 6, Hadith 66 : In what circumstances is it permissible to combine prayers according to Islamic teachings?

Ibn ‘Abbas reported that the Messenger of Allah (ﷺ) observed in Medina seven (rak’ahs) and eight (rak’ahs), i. e. (be combined) the noon and afternoon prayers (eight rak’ahs) and the sunset and ‘Isha’ prayers (seven rak’ahs).