Unfortunately; Fortunately

Fortunately they all had tenure.

Unfortunetly, this had no affect because nobody knew what "tenure" meant.

Fotunately, one of them looked it up in the dictionary and found out it meant they couldn't be fired.

Unfortunetly, the teachers were assasinated instead.

Unfortunately, this made them a lot more determined and of course undead.

(Melkor, I think you meant to write "fortunately"?)

Unfortunately, they were so shocked that they couldn't do anything.

Fortunetly, the teenage mutant ninja turtles came to help them.

Unfortuantely, a flying assasin-rabbit flew in and slaughtered all the ninjas.

Fortunately, someone volunteered to clean all the blood that spilled on the floor.

unfortunatly, the blood was front subjects with HIV, AIDS, and other horrible diseases. the person cleaning up the blood was not only infected, but he washed the rags in the sink where the water went and contaminated the entire city, starting an epidemic of HIV, AIDS, and other horrible diseases in the Greater Antilles and America

Fortunately, someone sewed all the found pieces of the turtles together, creating now an Extra Super Duper Ninja Turtle who could stop all the epidemics in the world.

Unfortunately, whichever genius made the Extra Super Duper Ninja Turtle, didn't consider making it immune to the diseases itself, so in an attempt to stop the diseases the Extra Super Duper Ninja Turtle caught one of them. And died.

Fortunately, after the Extra Super Duper Ninja Turtle died, the diseases were cleared out of the river.

Unfortunately, it was still in the lake. The one where all the little kids hang out....

Fortunately, the little kids decided that the lake was lame and hung out at the basketball court