Complex sentence: Oamaru was a parliamentary electorate in the Otago region of New Zealand, from 1866 to 1870,1881 to 1957, and then from 1969 to 1978.
Split into simpler sentences: Oamaru was a parliamentary electorate in the Otago region of New Zealand, during three periods between 1866 and 1978. The electorate existed three times: from 1866 to 1870,1881 to 1957, and then from 1969 to 1978.