This occurs when changing over from a medd letter to the first letter of a shaddah. The saakin letter occurs with 
and the mouth was busy emitting the lengthened letter, so then it is necessary at the change over from the medd to the saakin letter that occurs after it, we put an accent ( 
) in our recital to facilitate this change over. This allows us to comply with reciting the saakin letter with (with collision) that leaves an acoustical mark. The saakin letter then makes its presence known quite clearly. If the (collision) is weak the letter is then pronounced with a weak sound to such a degree that it may not even be heard. This is often heard from some people when they recite
, with one 
with a kasrah on it instead of the two written , the first saakinah, the second with a vowel; this mistake of pronouncing only one is due to not making the . Other examples of this the third circumstance of the are in:
Click here to listen to this word with the
Click here to listen to this word with the
In all these cases there is a medd letter followed by a shaddah, and we need to make an accent, or raise our voices slightly at the end of the medd, to make sure we pronounce both parts of the shaddah, the saakin letter and voweled letter.
The Fourth circumstance of 
in recitation of the Glorious Qur’an
This occurs when stopping on a word that has a hamzah as the last letter preceded by a medd letter or leen letter. The reason for 
here is so that the hamzah is not lost after the mouth was busy emitting the medd or leen letter. Remember, we do not stop on the hamzah with a sukoon when there is a tanween with a fathah on the hamzah when it is the last letter of the word; instead we stop with a 
, so there would be no then.
Examples:
The Fifth circumstance of in recitation of the Glorious Qur’an
This circumstance encompasses three different words in three specific locations in the Qur’an, when these words are read in continuation with the following word. These three words are all past tense verbs in the double form of the verb (which is an alif) followed by a sukoon. The is needed in these three places so the meaning of the verse is not confused. The is an indication that there is an alif indicating a double present, but it was dropped in pronunciation due to the Arabic rule forbidding two saakin juxtaposed letters to be recited together. Without the , the listener may think the verb is male singular instead of male double. The is used only when reciting these words in continuum with the next word, when stopping on the verbs the alif indicating a double is then pronounced because there is no longer the meeting of two saakin letters and there is no need for the since the reason for it has disappeared.
