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Graph these comma-separated phrases:
case-insensitive
between and from the corpus with smoothing of .  
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1750 - 1778 1779 - 1810 1811 - 1813 1814 - 1817 1818 - 1820 liberal system English
1750 - 1777 1778 - 1793 1794 - 1797 1798 - 1817 1818 - 1820 liberal principles English
1750 - 1775 1776 - 1789 1790 - 1791 1792 - 1817 1818 - 1820 liberal ideas English
1750 - 1774 1775 - 1801 1802 - 1805 1806 - 1815 1816 - 1820 liberal plan English
1750 - 1779 1780 - 1808 1809 - 1811 1812 - 1815 1816 - 1820 liberal policy English
1750 - 1791 1792 - 1806 1807 1808 - 1819 1820 liberal government English

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