1. An electronic document processing method, comprising steps of: acquiring an electronic template comprising a set of semantic items, wherein (i) candidate values of the set of semantic items and relations among a plurality of semantic items in the set of semantic items are associated with one or more electronic semantic codes, and (ii) the electronic template is associated with a natural language expression mode; receiving an electronic input value for at least one semantic item in the set of semantic items, wherein the electronic input value comprises one or more constituent values; generating a first electronic document comprising (i) a first set of electronic semantic codes corresponding to the electronic input value, (ii) the relations among the plurality of semantic items, and (iii) a second set of electronic semantic codes corresponding to the relations among the plurality of semantic items; and generating, based on the electronic input value and based on the natural language electronic expression mode, a second electronic document comprising the electronic input value.