Complex sentence: The club first played in the Chelmsford Mid-Essex League, before joining the Southend District league, where they remained until 1982 when the league merged with the Southend Borough Combination to form the Alliance League, which the club assumed membership of.
Split into simpler sentences: The club first played in the Chelmsford Mid-Essex League, before joining the Southend District league, where they remained until 1982. In that year, the league merged with the Southend Borough Combination to form the Alliance League, which the club assumed membership of.