Identifying function words

[davidjackson]

If we assume a direct mapping, then taking a romance example (Italian) at once brings up annoying counter examples that make a mockery of attempting to map functors in this fashion  Ie, how to distinguish between

e = and

è = is/are (third person singular of essere: to be)

To further complicate matters  when followed by a vowel initial word it's Ed, not e. And as, not a. Etc 
Similar to a/an in English. 
So we need to take into account the following word when creating our mappings. Duplication is unlikely to account for this  as this is purely a spoken preference which has worked its way into grammar.