It is very very basic:Express each of these statements using quantifiers. Then form the negation of the statement so that no negation is to the left of a quantifier. Next, express the negation in simple English. (Do not simply use the phrase It is not the case that.)
b) There is a student in this class who has chatted with exactly one other student.
I was able to correctly translate the statement, the answer being , where Q(x,y) represents, "x has chatted with y."
When I alter the statement by negating it, it becomes (this required a few propositional equivalences to get to this state.) The difference between my answer and the true answer is, that the disjunction is actually a conjunction.