Difficulty putting into words 'Universe of Discourse', Let $A =$ $\Bbb Z$ I am struggling with a particular concept, I'll lay it out how I think will best allow for an answer:
Let $A =$ $\Bbb Z$ be the set of all integers and the universe of discourse. 
Let B, be the set of even numbers

Let C, be the set of odd numbers

Let D, be the set of positive numbers

Let E, be the set of negative numbers

Now I would like the ability to be able to express the following Sets in words, to help my understanding of the topic:
A) $(A-B)$
B) $ C \cap D$
C) $\overline{(D \cup B)}$ 
Any help to express these sets in 'words' would be great, it has me stumped. 
Thanks!
 A: Your universe of discourse is the set of all integers. One property of integers is that they have a parity of either being even or odd. So if you exclude all even numbers from the set of integers, then you will be left with a set containing all odd numbers.
Hence, $A-B=C$, or using words, $A-B$ is the set of odd integers.
$\{...,-5,-3,-1,1,3,5,...\}$
On the other hand, $C \cap D$ is the set of odd positive integers, since you are taking the set of odd numbers, and the set of positive numbers, and intersecting them, meaning that you are looking at the numbers that both sets have in common, which are the positive integers that are odd. $\{1,3,5,7,...\}$
For part C, you have $D$, a set of positives, and $B$, a set of evens. If you want a set that contains neither even numbers nor positives, ie. $\overline{D\cup B}$, then your set becomes the set of odd negative integers. $\{...,-5,-3,-1\}$
To express the sets in words, simply think about what kind of elements the sets would contain (ie. their property with respect to the universe of discourse), and write that in words.
A: 1) $(A-B)$ is $\{x\in \mathbb Z| x\in A \cap x \notin B\}  \iff \{x\in \mathbb Z| x\in A \cap x \notin 2\mathbb Z\}$ 
This means the element $x$ found in the set is an odd integer.
2) $C \cap D$ means integers that are both positive and odd $\iff$ positive odd integers
3) $\overline{(D \cup B)}  \iff (\overline{D} \cap \overline{B})$ means numbers that are negative odd integers.
