English Grammar Review
Prepositions and Conjunctions

Coordinating Conjunctions

Conjunctions do two things: they join things and they explain relationships.

Consider the following examples:

(1) Buenos Aires has a rich cultural life, and it's a popular tourist destination.

(2) Buenos Aires has a rich cultural life, so it's a popular tourist destination.

(3) Because Buenos Aires has a rich cultural life, it's a popular tourist destination.

The conjunctions are highlighted in bold font.

In sentence (1) we have a coordinating conjunction. It joins two, complete-sentence clauses. But what does it explain? Not a lot. It explains that these joined things are probably similar in structure, and it hints that these things might be connected for a reason.

In sentence (2) we have another coordinating conjunction. It also joins two, complete-sentence clauses. But it explains something about the relationship between the clauses: "statement1 being true means statement2 is probably also true". It's a connection, but somewhat loose.

In sentence (3) we have a subordinating conjunction. It joins the clauses, but it also clearly explains a relationship: "statement1 being true causes statement2 to be true." It indicates a tight connection.

We will talk about subordinating conjunctions in the next lesson.

Coordinating conjunctions

Here they are:

and . but . or . yet . so

If you feel a strong need to memorize them, you could use the acronym A-BOYS as a mnemonic device. (You may find this useful in the next lesson.)

Coordinating conjunctions are normally used to join similar things: words to words, phrases to phrases, or clauses to clauses.

Mateo bought paper or pens.
[nouns]

Sofia sent and received emails.
[verbs]

Sebastian is quiet and reserved.
[adjectives]

Lucia proceeded slowly but steadily.
[adverbs]

Cordoba is across the plains and in the foothills.
[prepositional phrases]

Ms. Gonzalez got promoted, yet she keeps learning.
[clauses]

Attributes of coordinating conjunctions

Connection: Coordinating conjunctions usually form looser connections than other conjunctions do.

Placement: Coordinating conjunctions are placed in between the items joined.

Sebastian likes coffee, but he doesn't like tea.

Punctuation1: A coordinating conjunction that joins two words, phrases, or clauses has no need for a comma before the conjunction.

tables and chairs
[words]

in the office or on the road
[phrases]

what we say and what we do
[clauses]

Punctuation2: A coordinating conjunction that joins three or more items creates a series and requires commas between the items. But only the final conjunction is needed.

pencils, paper, and erasers
[words]

pens, and pencils, and paper, and erasers
[too many conjunctions]

at the meeting, in the office, and on time
[phrases]

get some rest, do your best, and explain the rest
[clauses]

Punctuation3: A coordinating conjunction that joins two independent clauses creates a compound sentence and requires a comma before the coordinating conjunction.

Mateo ate all the barbeque, so Sofia drank all the malbec.

The comma signifies a loose connection:

M ,   and   N.
M ,   but   N.
M ,   or   N.
M ,   yet   N.
M ,   so   N.

Correlative conjunctions

A subcategory of the coordinating conjunction is the correlative conjunction. These are actually paired conjunctions:

both X and Y

not only X but also Y

either X or Y

neither X nor Y

Usually, the meaning is the same as it is with the simple coordinating conjunction, but the correlative structure provides an additional degree of emphasis:

Mr. Lopez asked for facts and opinions.

Mr. Lopez asked for both facts and opinions.

Lesson: Coordinating Conjunctions
Module: Prepositions and Conjunctions
Course: English Grammar Review