Issue 994...
Issue 994: If during Salat a man listens to the verses making Sajdah obligatory, his prayer are in order, and on the basis of precaution, he should make a sign of Sajdah, and should also offer Sajdah after the prayers. Issue 995: It is not necessary to recite a Surah after Hamd in Mustahab prayers, even if that prayers may have become obligatory due to Nazr.
But, as for some Mustahab prayers like wahshat prayers, in which a particular Surah is recommended, if a person wishes to act according to the rules, he should recite the prescribed Surah.
Issue 996: While offering Friday prayers, or Zuhr prayers on Friday, it is Mustahab that after reciting Surah al-Hamd, Surah al-Jumu'ah should be recited in the first Rak'at, and Surah al-Munafiqun in the second Rak'at, and once a person begins reciting one of these Surahs he is not allowed as per obligatory precaution, to abandon it and recite another Surah in its place.
Issue 997: * If after Hamd, somebody begins reciting the Surah Qul Huwallah or Qul ya ayyuhal Kafirun, he cannot abandon it and recite some other Surah. However, if in Friday prayers and in Zuhr prayers on Friday, he recites one of these Surahs forgetfully, instead of Surah Jumu'ah and Surah Munafiqun, he can abandon it and recite Surah Jumu'ah and Surah Munafiqun, but the precaution is that he should not abandon that Surah after having read more than half of it.
Issue 998: If a person recites intentionally Surah Qul Huwallah or Surah Qul ya ayyuhal Kafirun in Friday prayers or in Zuhr prayers on Friday, he cannot, as an obligatory precaution, abandon it to recite Surah Jumu'ah and Surah Munafiqun, even if he may not have reached half of it. Issue 999: * If in Salat , a person recites a Surah other than Surah Qul Huwallah and Surah Qul ya ayyuhal Kafirun he can abandon that Surah before reaching half of it, and recite some other Surah.
But as a precaution, he should not abandon it after having reached half, and it is not permissible to resort to another Surah. Issue 1000: * If the person in Salat forgets a part of a Surah, or cannot complete it owing to helplessness, like very little time of Salat is left, or for some other reason, he can abandon that Surah and recite some other Surah, even if he may have reached half of it. This applies to Surah Qul Huwallah or Surah Qul ya ayyuhal Kafirun also.