George Washington's "olde English" is all wrong (in the Head Museum). Firstly, that style of English was archaic even by his time, so there is no reason for him to talk like that. Secondly, the grammar is incorrect. At various times he uses the wrong mode, tense, person, and number.
When Leela jumps on the sofa between Fry and Bender, Fry's arm goes through Leela's body as it moves down.
Nixon states that "computers may be twice as fast as they were in 1973" when in fact this is a great understatement as computers would be at least three thousand times faster.