Here’s a pledge encouraged by the American Speech Committee that made the rounds back in 1918, an astonishing medley of patriotism and linguistic purism:
I love the United States of America. I love my country’s flag. I love my country’s language. I promise:
1. That I will not dishonor my country’s speech by leaving off the last syllable of words.
2. That I will say a good American “yes” and “no” in place of an Indian grunt “um-hum” and “nup-um” or a foreign “ya” or “yeh” and “nope.”
3. That I will do my best to improve American speech by avoiding loud, rough tones, by enunciating distinctly, and by speaking pleasantly, clearly and sincerely.
4. That I will learn to articulate correctly as many words as possible during the year.
Courtesy of Geoff Nunberg’s Quotes page, where you will find many more fine citations (e.g., “We have all got to exert ourselves a little to keep sane, and call things by the same names as other people call them.” Middlemarch, Ch. LIV).