A [[non-standard word]] can belong to more than one [[semiotic class]] and each semiotic class may have different preferred realizations. For example, the sequence "1755" can be: - a year: The Lisbon earthquake of 1755 (seventeen fifty-five) - part of a phone number: 12 345 1755 (one, seven, five, five) - a money amount: € 1755 (seventeen hundred and fifty-five euros) - a measurement: 1755 km (one thousand, seven hundred and fifty-five kilometers) The classification of non-standard words may involve other natural language processing techniques, such as named entity recognition, to identify individuals, countries, cities, street names, and other proper names. For example: - King Charles III (third) - XXI century (twenty-first) - Chapter XXI (twenty-one)