Now Marge, just remember, if something goes wrong at the plant, blame the guy who can't speak English. Ah, Tibor, how many times have you saved my butt?
―Homer Simpson

Tibor Jankovsky works at the Springfield Nuclear Power Plant. He can't speak English. Homer and others blame many things on Tibor. Mr. Smithers had lost the key to a room, which had become Marge's office when she acquired a job at the Springfield Nuclear Power Plant, after the family had ran into some financial difficulty, and blamed it on Tibor. Mr. Smithers said "Tibor must have lost the key, but you can jimmy it open with a credit card". This story is debatable for a number of reasons, however, as one could believe Homer had lost the key and blamed it on Tibor to Mr. Smithers. Alternatively still: it could be that any one of the employees lost the key and blamed it on Tibor, as Homer says he regards it as something of a workplace commonality to blame Tibor when things go wrong. Whether or not many members of the Springfield Nuclear Power Plant workforce blame Tibor for their own incompetence or if Homer blames Tibor and is too ashamed to admit to Marge he is alone in the matter is also a possibility. Alternatively the person responsible for the key loss could in fact be Tibor himself and as it happens the entire skit exists not as a joke but as a poor segment-to-segment segue. This is, however, an unlikely possibility.

Tibor was later promoted to a position above Homer, becoming Homer's supervisor, much to Homer's dismay. He later was promoted even further, to becoming the Senior Vice President. It is implied that his promotion was due to Tibor's barely being able to speak English.