1. Setting off the introductory element of a sentence
Two Main Uses of Comma in English Writing
Another instance in which the comma is necessary is where it is used to set off the introductory elements of a sentence. We can illustrate this by considering that last sentence. The subject of the sentence is another instance in which the comma is necessary. We could have started the paragraph, however, with an introductory clause:
If we move on to the second use of the comma, we can consider another instance in which the comma is necessary to set off the introductory element of a sentence.
In this example, the introductory element is just a way of establishing a link ease the reader into the main points being made. The same thinking is in evidence when we use tiny verbal tags such as Of course or Well:
Of course, she came first in every race.
Well, if you have confidence in Smith, we can offer her the job.
More commonly, however, we use ‘prepositional words or phrases’ to set up the main sentence. Prepositions are words, mostly short ones that show how other words relate to each other. A prepositional phrase, therefore, is a phrase at the start of a sentence that eases the reader from one sentence to the next or eases the reader into a sentence. ‘Preposition’ literally means to go before’, establishing a position, as in these examples:
Around the world, five out of ten people consume alcohol.
Up on the roof, the tiles were showing signs of wear.
Near the seaside, the temperature is often lower.
After selling her business, she was a millionaire.
‘Why’, you might ask, ‘do we use a comma after these introductory phrases?’ The point is that it helps clarify the meaning of a sentence, the very slight pause in reading allowing the reader to shift from finding a position to focusing on the real substance of the sentence without confusion. The comma divides the information up so that the reader can absorb it in meaningful units. The rule to bear in mind, then, is a fairly simple one. At the beginning of a sentence, you might encounter an introductory or prepositional phrase that Is set off by a comma.
2. Additional and subordinate clauses at the end of sentences We often add another clause at the end of a sentence, most commonly a subordinate clause. It adds to the meaning of the main clause, but cannot Hand on its own. Here is a simple sentence:
Television programs for teenagers are usually embarrassing.
We might want to extend the sentence:
Television programs for teenagers are usually embarrassing, although some are excellent.
The comma is used before the subordinate clause in order to clarify the Weaning by making the sentence easier and clearer to read. The difficulty is that a comma is not always absolutely necessary. To some extent it depends upon you deciding whether a slight pause or change of direction needs to be signaled to the reader. If in doubt, include the comma. You should, however, always make sure that it is separating elements of a sentence; that is to say, most often it will appear at the start and/or end of a clause and not between the subject and verb unless an adverb has been inserted. In the example we have provided here, the person who got it wrong would probably write:
Television programs for teenagers are usually embarrassing although some are excellent.
There are two mistakes here, though they just involve the one comma. The first is the failure to insert the comma between clauses – that is after embarrassing-which is where it should come. Very often students sense a comma is needed but then – and this is the second mistake – they put it, as here, between the subject (Television programs for teenagers) and the verb (are). This is always wrong: The dog, bit the man is incorrect. It should be: The dog bit the man. As we noted above, the only time you separate the subject from the verb is when you insert an adverb or a phrase: The man, oddly enough, bit the dog in return.
Tags: elements of a sentence, English Basics, introductory clause, introductory element, introductory elements, introductory phrases, paragraph, prepositional phrase, prepositional words, uses of comma