I’m currently studying Modern Standard Arabic (al-fussha) which is derived from Classical Arabic. MSA attempts to follow the grammatical rules of the classical language, and thus differs from the colloquial Arabic dialects like Egyptian, Syrian, Palestinian, etc. MSA uses the Arabic alphabet although some different letters are used depending on the region and the pronunciations of these letters may differ greatly. For example, the letter that sounds like “j” in MSA sounds like “g” in Egyptian and some letters are not included in the MSA alphabet but exist in certain regions and are generally used to pronounce foreign or borrowed words.
One difficult aspect of learning Arabic is that short vowels are not required to be written so that the reader, at first glance, is not sure which vowels the word needs in order to be pronounced correctly. The reader must be aware of the context and meaning of the words in order to read them aloud.
There are 28 basic letters of the Arabic alphabet and while there is no distinction between upper- and lower-case as there is in English, some of the letters change form depending on where they occur in the word so that they may or may not “connect” to other letters. Certain letters change their shape a great deal and others not at all. Some letters are non-connecting in which case they do not connect to letters that follow them. Connecting letters connect to the letters before them and some connect to the letters after them as well. Remember that Arabic is read right to left so the “preceding” letter means the one to the right, not the left.
Connecting letters take four forms known as: initial, medial, final and isolated. The initial form is seen in letters that begin a word or follow a non-connecting letter, the medial form occurs between two connecting letters, the final form occurs at the end of a word following a connecting letter, and isolated forms occur at the end word after a non-connecting or when used by itself.
This is the letter ش (sheen) and it is pronounced like “sh”. The following examples show the letter in its four forms.
Initial: شكرا “Thank you” pronounced “shukran”. “shukran” is composed of the letters: ش-ك-ر-ا. As you can see some of these letters changed shape and ش lost its curly tail.
Medial: دمشق “Damascus” pronounced “dimashk”. In this instance, the letter “sheen” is connected to both of the following and preceding letters and it is written without the tail.
Final: ريش “Feather” pronounced “reesh”. Here, the letter “sheen” is last and while it is connecting to the preceding letter it has no following letter to which it connects and so it is written with the tail.
Isolated: فراش “Bed” pronounced “firash”. Because the letter ا “alif” is not a connecting letter, the letter “sheen” is isolated and is written as its dictionary/isolated form ش.