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.

Sofia sent and received emails.

Sebastian is quiet and reserved.

Lucia proceeded slowly but steadily.

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

Ms. Gonzalez got promoted, yet she keeps learning.

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

in the office or on the road

what we say and what we do

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

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

at the meeting, in the office, and on time

get some rest, do your best, and explain the rest

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