Corrected entry: In this episode, no one can read the Alien language on the note left by Leela's parents. However, this language has been posted on various signs throughout the series. It would be rather pointless for someone to make advertisements that no one can read.
As the power builds up in Bender, his left eye pops out, making him a cyclops, subsequently being eaten by the Cyclops eater. After the monster dies, Bender comes out, and has two eyes in the long shot, but puts his left eye back in the close up.