One who writes two letters, whether with his right hand or his left; whether of one character or of two characters; whether with two inks; in any language, he is liable. R’ Yose says: They declared [writing] two letters liable only because of mark-ing, for thus would they write on the boards of the Mishkan, to know which ones were mates. Rabbi [Yehudah HaNassi] said: We find a short name which is part of a long name, SHeM from SHiMon, or SHMuel, NoaCH from NaCHor, DaN from DaNiel, GaD from GaDiel.