Editing Interlingua (section)

===Free word-building===
Words can also be included in Interlingua by deriving them using Interlingua words and [[affix]]es; a method called '''free word-building'''. Thus, in the [[Interlingua–English Dictionary]] (IED), [[Alexander Gode]] followed the principle that every word listed is accompanied by all of its clear compounds and derivatives, along with the word or words it is derived from. A reader skimming through the IED notices many entries followed by large groups of derived and compound words. A good example is the Interlingua word {{lang|ia|nation}}, which is followed by {{lang|ia|national}}, {{lang|ia|nationalismo}}, {{lang|ia|nationalista}}, {{lang|ia|nationalitate}}, {{lang|ia|nationalisar}}, {{lang|ia|international}}, {{lang|ia|internationalitate}}, and many other words.

Other words in the IED do not have derivatives listed. Gode saw these words as potential word families. Although all derived words in the IED are found in at least one control language, speakers may make free use of Interlingua roots and affixes. For example, {{lang|ia|jada}} ('jade') can be used to form {{lang|ia|jadificar}}, ('to jadify, make into jade, make look like jade'), {{lang|ia|jadification}}, and so on. These word forms would be impermissible in English but would be good Interlingua.

====Word-building by analogy====
Gode and Hugh E. Blair explained in the [[Interlingua: A Grammar of the International Language|Interlingua Grammar]] that the ''basic principle of practical word-building'' is analogical. If a pattern can be found in the existing international vocabulary, new words can be formed according to that pattern. A meaning of the suffix {{lang|ia|-ista}} is 'person who practices the art or science of....' This suffix allows the derivation of {{lang|ia|biologista}} from {{lang|ia|biologia}}, {{lang|ia|physicista}} from {{lang|ia|physica}}, and so on. An Interlingua speaker can freely form {{lang|ia|saxophonista}} from {{lang|ia|saxophone}} and {{lang|ia|radiographista}} from {{lang|ia|radiographia}} by following the same pattern.

====Usefulness and clarity====
As noted above, the only limits to free word-building in Interlingua are ''clarity'' and ''usefulness''. These concepts are touched upon here:

Any number of words could be formed by stringing roots and affixes together, but some would be more useful than others. For example, the English word ''rainer'' means 'a person who rains', but most people would be surprised that it is included in English dictionaries. The corresponding Interlingua word {{lang|ia|pluviator}} is unlikely to appear in a dictionary because of its lack of utility. Interlingua, like any traditional language, ''could'' build up large numbers of these words, but this would be undesirable.

Gode stressed the principle of ''clarity'' in free word-building. As Gode noted, the noun {{lang|ia|marinero}} ('mariner') can be formed from the adjective {{lang|ia|marin}}, because its meaning is clear. The noun {{lang|ia|marina}} meaning 'navy' cannot be formed, because its meaning would not be clear from the adjective and suffix that gave rise to it.