Q: A person is performing 4 Rakats of Thuhr Fardh Salaah. After completing the Sajdah of the 4th Rakat, he forgets to sit for the last Qa'dah and stands up for a 5th Rakat. He begins with Qiraat and then realizes his mistake. What should he do?
A: At the point when he realizes his mistake, he should immediately return to Qa'dah, read Tashahhud, make Sajdah Sahu and then complete the Salaah as normal. [Shaami V 2: P 551]