The early stages of learning to write are described in the _Protagoras_ of Plato.[229] “When a boy is not yet clever at writing, the masters first draw lines, and then give him the tablet and make him write as the lines direct.” The passage has been variously interpreted. Some regard the master as merely writing a series of letters which the boy is to copy underneath. The word used in Greek for the master’s writing is ὑπογράψαντες [hypograpsantes], and it is significant that the word for a “copy” in this sense is a derivative of this word, ὑπογραμμός [hypogrammos]. Such a copy, corresponding to the phrases like “England exports engines” or “Germany grows grapes,” which are employed in English schools for this purpose, is extant.[230] It is a nonsense sentence designed to contain all the letters of the alphabet μάρπτε σφὶγξ κλὼψ ζβυχθηδόν [marpte sphinx klôps zbychthêdon]. If this rendering is correct, the master wrote a sentence of this sort on the tablets, and the boy copied it underneath. Others interpret the lines which the master draws on the tablet as parallel straight lines, within which the boy had to write. Just such a device is often employed in English copy-books. The word used for “lines,” γραμμαί [grammai], usually means “straight lines,” which supports this interpretation. But ὑπογραφή [hypographê], on the other hand, a derivative of ὑπογράφειν [hypographein], is used for irregular traces, _e.g._ a footstep,[231] and ὑπογράφειν [hypographein] itself is a technical term in Hellenic art for “sketching in” what is afterwards to be finished in detail. Consequently a third rendering of the passage makes the master draw a faint, rough outline of the various letters, and the boy has to go over them with his pen, marking the grooves in the wax deeper and filling in the details. For example, in England, the master might draw |·| and the boy go over the two vertical lines and draw in the other two, M. Thus all three interpretations are sensible and rest on good authority. But surely the master may be regarded as adopting all three processes, according to the intelligence of the pupils. For the beginner he would outline the whole letter, and leave him only the task of going over it again. Then he would gradually give less and less help, till the boy was capable of writing the letters with the assistance of the parallel lines alone. Finally these would be withdrawn, and the boy would be left to write his imitation of the copy without assistance. The phrase in Plato is purposely vague, and will include the whole of this process.