Complex sentence: In a well-known model of language planning by Einar Haugen, codification is only the second step, step one is the selection process, step three is the elaboration of vocabulary (especially technical terms) and step four the implementation of the changes in society.
Split into simpler sentences: In a well-known model of language planning by Einar Haugen, codification is only the second step. Step one is the selection process, step three is the elaboration of vocabulary (especially technical terms) and step four the implementation of the changes in society.