is unrelated to the word it modifies
The word "avail" (a) is not related to speaking. It means to profit or take advantage of. An example of the word avail used in a sentence is:
He availed himself of the opportunity to learn from his university professor.
The words "discourse", "interjection", and "voluble" are all related to speaking; each with a different meaning. The word discourse relates to a political discussion or written or spoken communication.
<span>The word "interjection" is used to express an emotion or sentiment on the part of the speaker. A good example is "Hey! Come back here." The interjection is the word "Hey". </span>The word "voluble" describes a person who speaks fluently, or talks incessantly.
Form good habits, know that you can still accomplish something despite the fact that there are several reasons not to or why you "can't", and know how to form good self-discipline for success.
Frontier is defined as 1) a line separating two countries, 2) the extreme limit of settled land beyond which lies wilderness, or 3) <span>the extreme limit of understanding or achievement in a particular area.
Right away we can cross out B because the wilderness is pretty close to a frontier. We can also cross out D because it doesn't make sense with the definitions given. So now we are left with A and C.
A is a funny misuse of the word; they probably meant to say "front." So, now we only have C. C is correct, and it makes sense because space does have an </span>extreme limit of understanding in science.
