Namaz main"RUKU" k baad or "SAJDEY" se pehle sakoon se seedha khara hona wajib hai. Is halat ko "QOMA" kehte hain. Issi trha dono sajdon kjdoon ke darmiansakoon se seedha baithna bhi "WAJIB" hai Is halat ko "JALSA" kehte hain
also you can..