'plainly-presented' originates from the combination of 'plainly' and 'presented'. 'Plainly' comes from the word 'plain', which originates from Latin 'planus', meaning 'flat, level'. 'Presented' comes from Latin 'praesentare', meaning 'to place before'.

'Plainly' evolved from Middle English 'plein', while 'presented' evolved from Old French 'presenter'.

Initially, 'plainly' meant 'in a flat or level manner', and 'presented' meant 'to place before'. Over time, 'plainly-presented' evolved to mean 'shown in a straightforward manner'.