salaah

Reciting behind the Imaam

Q: What is the correct way to pray the Salats of Zuhr and Asr behind the Imam? Also, please, explain what is the correct way to perform the third Rak'ah of Maghrib and third and fourth Rak'ah of Isha behind the imam. Should a Muqtadi (person praying Jamaat behind Imam) recite Fatiha and Surah in the first two Rak'ahs of Asr and Zuhr and then recite Fatiha only in the last two Rak'ahs of Zuhr and Asr? Also should the Muqtadi recite Fatiha in the third Rak'ah of Maghrib and in third and fourth Rak'ah of Isha or should he stay quite? You I have to read inni and sana before surah fatiha in jamaat and in sunnat prayers shall I recite inni and sana? While performing prayer alone of maghrib what to recite in the third rakat?

Intending to perform nafil salaah or to keep nafil fast

Q: In the one instance, one makes intention to keep a nafil fast or to perform a nafil salaat. But then, at the appropriate time, one changes one’s mind and does not keep the fast or perform the nafil salaat. In the second instance, one had already commenced performing nafil salaat but when one’s wudhu broke, one did not renew one’s wudhu and abandoned performing the nafil salaat. In the first instance, is it now mandatory to fast and perform the nafil salaat one had intended to perform? And, in the second instance, does performing the abandoned nafil salaat also become mandatory?