Sun and Moon Letters - Rule

Rule

When followed by a sun letter, the l of the Arabic definite article al- assimilates to the initial consonant of the following noun, resulting in a doubled consonant. For example, for "the Nile", one does not say al-Nīl, but an-Nīl. When the definite article is followed by a moon letter, no assimilation takes place.

Sun letters represent all coronal consonants except ج ǧīm (see below). Since the article al- ends in a coronal consonant, it lends itself to assimilation with these sounds.

The sun and moon letters are as follows:

Sun letters
t d r z s š l n
Moon letters ء ه
ʾ b ǧ ʿ ġ f q k m w y h

Read more about this topic:  Sun And Moon Letters

Famous quotes containing the word rule:

    To rule is not so much a question of the heavy hand as the firm seat.
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    The rule for hospitality and Irish “help,” is, to have the same dinner every day throughout the year. At last, Mrs. O’Shaughnessy learns to cook it to a nicety, the host learns to carve it, and the guests are well served.
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