> Are they best expressed in four lette words as well?
Generally, no. Expletives are typically most effective I find when used to either denote some unpleasantness... or as a modifier to denote "powerfully emotionally affective and shocking extreme."
I *dare* anyone to come to Utah in June, camp out near Thiokol, and watch the planned RSRM static test and *not* use words akin to those I used: "Holy Shi..."
But for negative situations, nothing sums things up quite as succinctly as a simple four-letter muttering - or yell. Imagine Kerry had won the election. What, no expletives? Be honest...
In Utah, you would also hear expressions like "holy flip" and "fetch!" which, I would have to admit, are silly imitations.