Complex sentence: The City continued to grow as the City annexed portions of Whittier Boulevard and East Whittier, the 1961 annexation added over 28,000 people to the population, bringing the total to about 67,000.
Split into simpler sentences: The City continued to grow as the City annexed portions of Whittier Boulevard and East Whittier. The 1961 annexation added over 28,000 people to the population, bringing the total to about 67,000.