Linguistically, it has a syllabic usage for šum, as well as for tag, tak, and taq. It can also be used alphabetically for š, m, t, g, k, or q, and also as a replacement for the four vowels, of a, or e, or i, or u.
Epic of Gilgamesh usage
The šum sign usage in the Epic of Gilgamesh is as follows: (šum, 34 times, tag, 2, tak, 23, and taq, 7 times).[1]
Amarna letters usage
A common usage of the šum cuneiform in the Amarna letters is for the Akkadian word šumma,[2] (), for English if. In the letters the strife with the Habiru, taking over cities, (city-states), the reference is, "If the pharaoh doesn't send the archer force, our town is lost!".
Gallery
šumma, last line, ma more visible than šum (line 57, of 66)
after šumma, 4 cuneiform characters are used. In the Amarna letters, – they are translated in English, as "there-is-not".
Line 51 is the second line from top, and ma is easily visible; the right part of šum is visible; I put a damaged #, marker at the cuneiform spot in line 51, EA 288.