This lesson starts the group of characteristics for certain letters that have no opposites, meaning when a letter or a group of letters has a characteristic of this type, there is no antithesis characteristic for the rest of the letters.

The Whistle

Its linguistic definition: Sharpness of sound

Its applied tajweed meaning:  Sharpness in the sound of the letter produced from it transversing through a tight passage.

Its letters: There are three letters that have this characteristic: , , and 

This sound is not a forced sound, but one that should come out naturally with the letters.  Some may have difficulty producing this characteristic if they have a large over bite of the upper teeth.  This can be overcome if the lower jaw is protruded so that the upper and lower teeth align.  Another reason for the incorrect muting of this characteristic is if the tip of the tongue is pressed up with force on the plates of the teeth.  If a small space remains between the tongue and the plates, the whistle can be emitting easily.

Imam Al-Jazaree said:

The Ease

The linguistic definition: Easiness
 
Its applied tajweed definition: Emitting the letter from its articulation point with ease without effort from the tongue.
Its letters: The  and the  of leen, meaning  the  or  with a sukoon preceded by a fat-h. 

Imam Al-Jazaree said:

[and the “leen”, wow and ya’ with a sukoon and both have a fat-h before them]

The Deviation

Its linguistic definition: Drifting

Its applied tajweed definition: Drifting of the sound of the letter as it leaves [its articulation point] due to the incomplete running caused by the tongue turning from its path.

Its letters:  and

The tip of the tongue sticks at the articulation point of the ,  (as in the characteristic of ), the sound then deviates off the sides of the tongue (as in the characteristic of ), which is used also for the articulation point.
 The  sticks at the left and right of the very tip to the second part of the articulation point ie. the gums of the two front teeth (as in) ;  the sound then needs to escape so that there will not be repetition or trilling ().    A small space at the very tip of the tongue is made so the sound can escape out the mouth (as in ) and trilling of  is therefore avoided. The tip of  tongue is somewhat cupped for this small space to occur in the middle of the tip.

 This is the reason both of these letters have the characteristic of  instead of or . 

Imam Al-Jazaree said:

[and the "deviation" is applied, in the laam and the ra']

Next lesson will, insha' Allah, continue with the characteristics that have no opposites.