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Compound Sentences

We saw in sentence structure that a compound sentence is two (or more) independent clauses joined by a coordinating conjunction or semicolon. So a compound sentence is like two or more simple sentences added together. A compound sentence does not contain any dependent clauses.

Joining Compound Sentences with Coordinating Conjunctions

Usually, we join independent clauses with one of the seven coordinating conjunctions.

independent clausecoordinating conjunctioncoordinating conjunctionindependent clause

The term coordinating conjunction sounds complicated, but in fact there are only seven of them and they are all short, one-syllable words: ForAndNorButOrYetSo — remember them with the mnemonic FANBOYS.

The most common of these coordinating conjunctions are and, but and or, in that order. Note that a comma (,) must come before the coordinating conjunction except when the clauses are short (in which case the comma is optional).

independent clausecoordinating conjunctionindependent clause

and

The and conjunction is the most common conjunction. It has several uses.

but

We use the but conjunction to introduce a clause that contrasts with the preceding clause, for example: Mary ran fast, but she couldn't catch John.

or

We use the or conjunction to join two alternative clauses, for example: Will Mary go, or will John go?

nor

We use the nor conjunction to join two alternative clauses when the first clause uses a negative such as neither or never. In this case both clauses are untrue or do not happen, for example: Mary never wrote the letter, nor did she call him. (Note the inversion of subject and auxiliary: did she.)

for

We use the for conjunction (meaning something like because) to join two clauses when the second clause is the reason for the first clause, for example: He felt cold, for it was snowing.

yet

The yet conjunction is similar to but. It means something like but at the same time; but nevertheless; but in spite of this. As with but, there is a contrast between the clauses, for example: I have known him for a long time, yet I have never understood him.

so

The so conjunction means something like therefore; and for this reason. We use so to join two clauses when the first clause is the reason for the second clause, for example: He was feeling sick, so he went to the doctor.

Note that when using a coordinating conjunction, you can (if you wish) remove any subject word and modal auxiliary from the second clause. (This is not possible with subordinating conjunctions.)
  • He's already had three beers, and now he wants another one. correct
    • He's already had three beers and now wants another one. correct
  • You can take a train, or you can take a bus. correct
    • You can take a train or take a bus. correct

Joining Compound Sentences with Semicolons

Occasionally, we join independent clauses with a semicolon (;).

independent clausecoordinating conjunctionindependent clause

Joining Compound Sentences with Conjunctive Adverbs

We can also join independent clause with words and phrases like moreover, however, at least (conjunctive adverbs). In this case, the conjunctive adverb must be preceded by a semicolon (;) and followed by a comma (,).

independent clausecoordinating conjunctionconjunctive adverbcoordinating conjunctionindependent clause

Look at these examples:

How to join independent clauses
comma + coordinating conjunction Independent clause , for
, and
, nor
, but
, or
, yet
, so
independent clause.
semicolon ;
semicolon + conjunctive adverb + comma ; moreover,
; however,
; indeed,
; therefore,
; at least,

The table shows all seven coordinating conjunctions, and a few conjunctive adverbs as examples.

Do not try to join independent clauses with a comma alone—that's impossible!
  • John drank coffee. Mary drank tea. correct
  • John drank coffee, Mary drank tea.
  • John drank coffee, and Mary drank tea. correct
  • John drank coffee, but Mary drank tea. correct
  • John drank coffee; Mary drank tea. correct

Compound Sentence Examples

Now look at some more examples showing compound sentences and coordinating conjunctions or semicolons in context.

Compound Sentences with Coordinating Conjunctions

Compound Sentences with Semicolons

Compound Sentences with Conjunctive Adverbs

Compound Sentences in Famous Quotations

Here are some examples of compound sentences in quotes from famous people and sources.

Compound Sentences in Sayings

These compound sentence examples come from everyday sayings and proverbs in the English language.