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Q 11: Sometimes I go to the Masjid (mosque) after the end of Salah (Prayer) and see a man praying alone but I do not know whether he is offering an obligatory or supererogatory Salah. Do I have to wait until he finishes and then pray with him?

A: You can ask him whether he is offering an obligatory or supererogatory Salah and he may beckon you to join him or not. There is nothing wrong either way, if you join him without first asking him, whether he is offering an obligatory or supererogatory Salah. After he announces Taslim (salutation of peace ending the Prayer), you should stand up and complete your Salah.