Google Books Ngram Viewer

Graph these comma-separated phrases:
case-insensitive
between and from the corpus with smoothing of .  
Search in Google Books:

1840 - 1946 1947 - 1996 1997 - 2000 2001 - 2004 2005 - 2009 should do is go English
1840 - 1876 1877 - 1942 1943 - 1947 1948 - 1983 1984 - 2009 should do is to go English
1840 - 1942 1943 - 1974 1975 - 1978 1979 - 2000 2001 - 2009 must do is go English
1840 - 1899 1900 - 1906 1907 - 1910 1911 - 1980 1981 - 2009 must do is to go English

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