Correctly Punctuating Compound Sentences

The below extract is taken from PETAA bestseller, A New Grammar Companion, 2nd Edition, written by Beverly Derewianka.

Compound sentences consist of two or more independent clauses. Each of these clauses is capable of standing on its own and conveying a message. Each has equal status and provides equally important information. These clauses may be linked together in a sentence using such words as 'and', 'but', 'or', e.g.:

He climbed into bed independent clause 
 and he fell fast asleep. independent clause
   
 Susan walked home  independent clause
 but the others caught the bus. independent clause 
   
 You could ring him at work independent clause 
 or you could try him at home.

 independent clause

 

Troubleshooting

Students often have trouble knowing how to punctuate compound sentences. A common error is to join them with a comma instead of a conjunction. This is sometimes called a 'comma splice':

Incorrect: I was late, I caught a taxi.

Correct: I was late so I caught a taxi.

A semi-colon (if the relationship is tight) or a full stop can be used instead of a conjunction, e.g.

I was late; I caught a taxi.

I was late. I caught a taxi.