Based on the clue 'a horse is a horse of course of course and no one ...', what is the answer?

Based on the clue 'a horse a horse my kingdom for a horse', what is the answer? Based on the clue 'a horse a horse my kingdom for a horse', what is the answer? What is associated with: a horse born december 31 1998 became a yearling on this date? Based on the clue 'a horse has got to learn to stand on his own four ...', what is the answer? What is associated with: a horse named comanche survived this mans june 1876 last stand? Based on the clue 'a horse or a person impatient at being held back i...', what is the answer? Based on the clue 'a horse or a salamander but not a human or a snake', what is the answer? Based on the clue 'a horse racing enthusiast so called for his tracks...', what is the answer?