The concept of nexus It is used in different ways. In the field of grammar , the term allows to refer to the element that join sentences, phrases and / or words through a syntactic function.
A adversative nexus is he who establishes a link by opposition . These terms or phrases relate two statements that, by their meaning, result opposites .
Also called adversative conjunctions , the adversarial links can establish a total or partial contrariety. This has to do with the restriction or with the correction which is introduced from the nexus.
By example : “I would love to accompany you to visit your mother but I have to work”. In this sentence we find two fragments (“I would love to accompany you to visit your mother” and "I have to work"), united by the adversary nexus "but". This marks an opposition between the desire of the speaker (“I would love to accompany you to visit your mother”) and the real possibilities of realizing it ("I have to work"), linked by adversative conjunction ("but").
Let's look at another case: “I already decided that I will quit my job, although I still have not defined when I will do it”. Here is the adversative link "though" which allows the link between two ideas (“I already decided that I will quit my job” and "I still haven't defined when I will"). The person has a decision made (he will resign from his job), but he still does not know when he will make the decision (that is, when he will resign). The adversarial link, therefore, marks the opposition between the plan or project and the effective development of the action.