Fixes w3c#51.

Per the 2024-03-28 teleconference, I modified the description of
_tanwin_ using @ntounsi's suggested text.

I modified the suggested text slightly:
- replacing 'i.e.' with 'that is'
- replacing NOON with IPA 'n' (per @r12a)
- minor English edits

Per Richard's comment, I didn't include 'madd'.

index.html

@@ -450,7 +450,7 @@ <h2>Glossary</h2>
 <div class="letter_anchor" id="t">T</div>
 
 <p><dfn class="lint-ignore export">Tashkil</dfn>. An Arabic script mark that indicates vocalization of text or other types of phonetic guide which indicate pronunciation, such as in <span class="codepoint" translate="no"><bdi lang="ar" dir="rtl">&#x062B;&#x064E;</bdi><span class="uname">U+062B ARABIC LETTER THEH</span> + <span class="uname">U+064E ARABIC FATHA</span></span>,
-pronounced <span class="ipa">θa</span>. These include several subtypes: <span class="name">harakat</span> (short vowel marks), <span class="name">tanwin</span> (postnasalized or long vowel marks), <span class="name">shaddah</span> (consonant gemination mark), and <span class="name">sukun</span> (to mark lack of a following vowel). <strong>A basic Arabic letter plus any of these types of marks is never encoded as an atomic, precomposed character, but must always be represented as a sequence of letter plus separate combining mark.</strong> For example, <span class="codepoint" translate="no"><bdi lang="ar" dir="rtl">&#x0647;&#x0670;</bdi><span class="uname">U+0647 ARABIC LETTER HEH</span> + <span class="uname">U+0670 ARABIC LETTER SUPERSCRIPT ALEF</span></span> pronounced <span class="ipa">ha</span>, is an example of a letter plus tashkil combination in Arabic (cf. the use of that diacritic in a precomposed Uighur letter).  See <a href="https://www.unicode.org/versions/Unicode13.0.0/ch09.pdf" target="_blank">Chapter 9</a> of the Unicode Standard. See also [=ijam=].</p>
+pronounced <span class="ipa">θa</span>. These include several subtypes: <span class="name">harakat</span> (short vowel marks), <span class="name">tanwin</span> (postnasalized, that is, an extra <span class="ipa">n</span> sound at the end of a noun marked by a double harakat), <span class="name">shaddah</span> (consonant gemination mark), and <span class="name">sukun</span> (to mark lack of a following vowel). <strong>A basic Arabic letter plus any of these types of marks is never encoded as an atomic, precomposed character, but must always be represented as a sequence of letter plus separate combining mark.</strong> For example, <span class="codepoint" translate="no"><bdi lang="ar" dir="rtl">&#x0647;&#x0670;</bdi><span class="uname">U+0647 ARABIC LETTER HEH</span> + <span class="uname">U+0670 ARABIC LETTER SUPERSCRIPT ALEF</span></span> pronounced <span class="ipa">ha</span>, is an example of a letter plus tashkil combination in Arabic (cf. the use of that diacritic in a precomposed Uighur letter).  See <a href="https://www.unicode.org/versions/Unicode13.0.0/ch09.pdf" target="_blank">Chapter 9</a> of the Unicode Standard. See also [=ijam=].</p>
 
 <p><dfn data-lt="text processing language" class="lint-ignore export">Text-processing language</dfn>. The language in which a specific range of text is actually written. This needs to be declared so that user agents or applications that manipulate the text, such as voice browsers, spell checkers,  style processors, hyphenators, etc., can apply the appropriate rules to the text in question. So we are, by necessity, talking about associating a <em>single</em> language with a <em>specific</em> range of text. Contrast this with [=language metadata=].</p>