Complex sentence: Similarly, use of word'Central' instead of'Federal' and term'Superior' are also legacy of past these were relevant when there was Central Government under 1956 constitution and classes existed in civil service.
Split into simpler sentences: Similarly, use of word'Central' instead of'Federal' and term'Superior' are also legacy of past. These were relevant when there was Central Government under 1956 constitution and classes existed in civil service.