Conversation so far:
When was John Belushi on Saturday Night Live?
John Belushi was one of the seven original cast members of the NBC sketch comedy show Saturday Night Live in 1975.
How long was John Belushi on Saturday Night Live?
Over his four-year tenure at SNL, Belushi developed a series of successful characters.

Question: What were his well known characters?
Self-contained rewrite: What were John Belushi's well known characters on Saturday Night Live?