A Punctuation mark is any symbol such as comma, hyphen, exclamation mark, semi-colon, or full stop which is used in a sentence to help in clearly understanding the sentence and, in turn, the writer’s intent.

Punctuation marks can make or mar the meaning of a sentence. They can be used either to make the sentence more attractive and emphasizing, or to completely destroy the intended meaning of the sentence. Four punctuation marks: comma, colon, hyphen and apostrophe prove to be very powerful in this aspect. Let us discuss on how they can alter the meaning of the sentence.

COMMA

A comma is used in many instances, though it is commonly used to seperate items in a list. The importance of a comma, especially in short sentences, is obvious from the following classic illustration of a judge's verdict.

Pardon impossible, to send to jail

Pardon, impossible to send to jail

The judge actually meant the first sentence, but as per what he has written (the second sentence), the jailors followed it and the convict was set free.

Likewise, consider the following two sentences. The intended meaning is that a person named Krishna has stolen the pen belonging to Ram.

“Ram, Krishna has stolen your pen.”

“Ram Krishna has stolen your pen.”

The meaning is changed in the second sentence due to the omission of comma.

COLON

As we know, the colon is generally placed before an independent clause, to denote a definition, to show that a person is starting a dialogue, or to introduce a list.

The following two pairs of sentences illustrate the significance of the colon in maintaining the intended meaning of the sentence.

Ram: “Krishna has come before Susan.”

“Ram Krishna has come before Susan.”

There is one thing that a man cannot live without: hope.

There is one thing that a man cannot live without hope.

In both cases, the first sentence has the intended and proper meaning.

HYPHEN

This is used with certain compound adjectives, with prefixes, and to separate non-essential clauses in a sentence.

The importance of the hyphen or dash is easily recognised in the following pairs of sentences. The first one demonstrates the improper placement of the hyphen;

You will required to work twenty four-hour shifts.

You will required to work twenty- four hour shifts.

while the second is a funny illustration of  the wrong usage of the hyphen.

The man eating cakes sat in the garden.

The man-eating cakes sat in the garden.

APOSTROPHE

The apostrophe is another punctuation mark which is inevitably used to denote possession. It would create confusion, if not correctly used.  This is demonstrated through the following two sentences.

The prisoner`s pen is lying on the table (implies that the pen belongs to one prisoner)

The prisoners’ pen is lying on the table (implies that the pen belongs to all the prisoners)

To summarise, I would like to point out the following example which further shows how a single sentence can be made to mean differently by changing the punctuation.

1.     Ram? He is a nice boy. (implies that Ram is a nice boy)

2.     Ram: He is a nice boy. (implies that Ram is telling that somebody is a nice boy)

3.     Ram, he is a nice boy. (implies that someone is telling Ram that someone else is a nice boy)

4.     Ram-he is a nice boy. (here, it creates the impression that Ram-he is another person and that Ram-he is a nice boy)