Learn Tajweed with Yasir Qadhi - The Noble Emissaries (As-Safara Al-Keram)
Episode 13 -- Idh-haar (Clarity)
A series about 'tajweed' and the art of reciting the Qur'an
(youtube by : khalifahklothing - here
Any ghunnah is held for two harakas.
Letters of Idh-haar (when a nun sakinah or tanween is followed by one of these letters, simply pronounce the nun sakinah or tanween crips and clear) -- any letter from makhaarij al-halq