Semantic characteristics

§ 251. Unlike prepositions, most conjunctions usually retain their specific meaning,

No one was pleased when he came.

No one would be pleased if he came.

No one was pleased because he came.

No one was pleased though he came.

Exceptions are those conjunctions which may be used in more than one function (that, if, whether, as). Of these the conjunction that possesses the most vague semantic content.

According to their meaning (or rather the semantic relation they express) all conjunctions fall into two types: coordinating conjunctions and subordinating conjunctions.

Coordinating conjunctions express copulative, disjunctive, adversative and causative-consecutive connections. These four main types of coordinative connection allow of different shades of meaning,* depending on the context. Thus copulative conjunctions (and, nor, as well as, both... and) denote not only simple addition, but sometimes express opposition, explanation, consequence. Nor expresses copulative connection and negative meaning at the same time, it very often correlates with negation in the preceding clause.

* See also the paragraph on conjuncts which are more specialized connectors, expressing a more specific connection.

He didn't doubt it for a moment, nor had he any fears about the possible turn of the events.

Note 1:

The coordinating conjunction and may be used in a somewhat different function if it joins the same nouns;

the effect may be to suggest that different types of persons or objects should be distinguished:

There are teachers and teachers. (There are good and bad teachers.)

If the noun is repeated more than once, the effect is to suggest a large number:

There were faces and faces and faces all around him.

The repetition of verbs produces an effect of continuous action or of increase in degree:

He talked and talked and talked.

Note 2:

If the pronouns you and I, or their case forms are joined by the conjunction and, conventions of politeness require that you should always come first:

you and I; you or me; you and they; you and them.

The disjunctive conjunctions or, otherwise denote a choice between two alternatives.

I’ll call on you on Saturday or on Sunday.

Did it matter where he went, what he did, or when he did it?

The adversative conjunctions but, not that denote contrast or contradiction.

He was tall but did not look it because of his broad shoulders.

They were silent, but there was no resentment on their faces.

There is only one causal conjunction for, which denotes reason or cause, and one resultative conjunction so.

He was never in the know of things, for nobody told him anything.

It was Saturday, so they were back from school early.