It is hopeless to attempt in any serious way to punctuate your prose correctly if you have no idea what kind of sentence you are dealing with (and therefore how it is put together).

There are only three kinds of sentences and anyone can tell which is which if he or she can identify the main verb in a sentence. That is the only requirement. (The only thing you must remember is that an -ing verb cannot be a main verb unless it is accompanied by another verb and neither can an infinitive like "to fly"/"to speak"/"to reply.")

All main verbs are presented in bold type.

A SIMPLE SENTENCE has one main verb and one subject. As a shorthand, I will represent it this way: SV. Simple sentences can be very short, as in

The sky fell.

or very long, as in

The longest-running story in the history of modern television resembled nothing so much as a warmed-over rehash of the world's greatest epic: The Last Freak Show, a heart-wrenching story of love, lust, laughter, longing, and looniness.

Here are a few examples that are perhaps not so obvious.

Tales from the Backwoods, by Jonathan Q. Sudbury, sold out in three weeks.
(Want an explanation?)

Flying in the face of tradition can be dangerous. In doubt?

Now, let's try another one.

Which would you prefer, a thimble or a kiss?

You know this. A question requires the inversion of subject and verb (or at least one of the verbs). Who "would prefer"? You, of course. The rest is irrelevant.

Now, there is one possible complication, but it's not very complicated. A simple sentence may contain EITHER multiple subjects OR multiple verbs (seldom both). However, they must be arranged so that all the subjects come before the verb(s) (SSVV--not SV/SV).

The poor old man tap danced, yodeled, and played the accordion. SVVV

The skateboarders skated to the top of the steps, leapt into the air, and landed in the street. SVVV

The poor old man and the silly young woman were an ill-matched pair. SSV

Jennifer and Sally baked cookies and made spaghetti sauce. SSVV

(BUT NOT Jennifer baked cookies, and Sally made spaghetti sauce. SV, SV--that would make a compound sentence, but more of that below)

The easy thing about simple sentences is that they present NO punctuation problems. You only have to know what they are so I can explain what other kinds of sentences are.

With me so far? OK, a COMPOUND SENTENCE is one you write frequently (you don't have to know anything about grammar to write correct sentences much of the time. It's only those few instances where you mess up that you need me for.) I will represent it thus: SV/SV. I use the slash (virgule) because there is more than one way to punctuate a compound sentence. A compound sentence (like a compound in chemistry or a compound fracture/verb/interest) has at least two parts. In other words, you can take two simple sentences (SV and SV) and make them into one longer sentence (SV/SV).

1. I hate pizza. I love death by chocolate. (SV. SV.)

2. I hate death by chocolate, but I love brownies. (SV, but SV.)

3. I love death by chocolate; I love brownies; I love all desserts! (SV; SV; SV.)
(Some like it hot; some like it cold; some like it in the pot, nine days old.)

Now pay attention: the difference between 2 and 3 is that 2 contains ", but" where 3 contains ";" It therefore makes sense to think of

rather than simply as the connectors between the two halves of number 2 (SV, and SV). In other words, if two sentences (and you know that because there are two main verbs) are put together with a conjunction (you don't have to know the word) like and, but, or,

Now, let's try a few others:

Do you want an orange, or would you rather have a peach?

She hated walking the dog, yet she would not trade him for a cat.

If you don't know how to punctuate a sentence, stop and think about the main verb before you do anything else, and then, once you've found it, decide what kind of sentence you have on your hands.

When you know what kind of sentence you're dealing with and how it is put together, you will know how to punctuate it, and you will never make serious mistakes again.

N.B.: Sometimes words "like," "yet," "so," "because" can act like and/but/or.

Jon has a hundred CD's at least, yet he never plays one.
Writing is a difficult subject, so many students put off taking Composition.

And then there is the semicolon:

New York is a busy industrial city; thousands of truck move through it every day.

By the way, why would you want to use a semicolon when you could choose some other way to write your sentence? Because it is particularly well suited to two ideas that fit together very closely like those in the last example; it is also good for two ideas that are parallel, as in: Students who have high grade point averages tend to belong to honor societies but not to belong to many other clubs; students who participate in a variety of extracurricular activities tend to have slightly (but only slightly) lower grade point averages.

"Students who . . . ; students who . . . . SV;SV, see? (There is no evidence that this is true. I just had to make up a sentence.) As you can see from this example, this is a good kind of sentence to write when you want to present a comparison or parallel of some kind.

Now check this one out:

Students are willing to work hard; however, they hate to work on trivial assignments.

DON'T get confused by the "however." "However" is NOT like and/but/or.

Want me to prove it?

You can write

Students are willing to work hard; however, they hate to work on trivial assignments.
Students are willing to work hard; they, however, hate to work on trivial assignments.
Students are willing to work hard; they hate to work on trivial assignments, however.

You can not write

Students are willing to work hard, but they hate to work on trivial assignments.
Students are willing to work hard, they, but, hate to work on trivial assignments.
Students are willing to work hard, they hate to work on trivial assignments, but.

Doesn't work so well, does it? "However" is not the same kind of linking word as and/but/or, so you cannot simply use a comma in sentences like this (SV, SV just doesn't make it.) To put it more bluntly,

SV, SV is never correct.

"Nevertheless" works exactly like "however":

Snakes are easy to take care of; nevertheless, I don't want one.

Finally, the COMPLEX SENTENCE, which I represent thus: + S + V +
(+ represents a dependent clause or clauses, which can occur almost anywhere in a sentence)

"Yikes! Dependent clauses! I never could get stuff like that straight!"
Never fear; the doctor is near! (Compound sentence, see?)

Anyway, all you need to know to spot the feared "dependent clause" is that it begins with a word like one of the following:

LOOK at this list. You can think of more words that are used like these to add to it. Add three or four. (They start with capital letters because you will very often find them at the beginnings of your sentences.) Anything that contains a SV but begins with a word like one of these can't be a main clause because it can't stand by itself as a complete sentence
("If you ask me . . ."--for instance). It depends on something else--the real main clause/main verb ("If you ask me, he is a winner.").

Now, there are a few other words that introduce dependent clauses, words that often trip writers up:

Whenever you encounter one of these words followed by a subject/verb, you know you DON'T have a main clause (or a main verb) on your hands. (I will mark these "fake" main verbs with small letters to show you where they are.)

Now, have a look at these, and look at the code at the end of each one that shows you where the dependent clause (+) comes in relation to the subject and main verb:

Although I love the theater, I loathe the movies. (+SV)

I would prefer an apple, since I don't like oranges.(SV+)

Mortimer, who seldom went out, always wore a coat indoors. (S+V)

A man who loves women will always come to a bad end. (S+V)
("A man who loves women" is the subject, so "loves" can't be a main verb.)

I don't know which he wants more, a wife or a housekeeper. (SV+)

This is also possible:

While high school may be easy, college is both serious and difficult. (+SV)

While high school may be easy, both college and life are tough. (+SSV)


I should also mention that you can put two kinds of sentences together to make a COMPOUND-COMPLEX SENTENCE (it's easy: a combination of the two):

Roses are red; violets are blue, except when they are white. (Now look at the code: SV; SV+)

I think football is more fun because it is a team sport, but I like tennis better, even though I don't play very well, because I like white uniforms. (SV+, but SV++)

Now for a really complicated one (the kind that you write--just wait and see):

Given that he has never performed well under pressure, and taking into account that he does not tend to follow through on his promises, even though he has promised to marry you, and he has given you a ring, I doubt that he will go through with the marriage; I think you will be disappointed. (++++SV; SV.)

And so on and on...


Now, for the simplest punctuation lesson of all time. . .

The Comma

1. Use commas between items in a series, including one before the "and." FOR EXAMPLE

2. Use a comma when two or more words are used to describe the same noun. FOR EXAMPLE

3. Use a comma before the conjunction (and/but/or) in a compound sentence (but don't forget the conjunction). FOR EXAMPLE

4a. Use a comma after a sentence opener or before an afterthought. The opener may be a clause (a dependent clause [+SV] beginning with Although, If, Since, While, etc.) or a phrase (such as: In the old days,... OR As a matter of fact,...). An opener is anything that comes before the subject of the sentence. FOR EXAMPLE
4b. Use commas before and after any other kind of parenthetical expressions (i.e., anything that could be left out without destroying the sentence). There are many kinds of parenthetical expressions. FOR EXAMPLE

That's it. Just eliminate all other commas. It might help to remember, too, that you never place a single comma between the subject and the verb [S,V]. Understand these four rules (the first two are utterly simple), and you're all set.

The only other punctuation confusion that may arise is that between the semicolon (compound sentences, remember?) and the colon. Just remember: the semicolon is a red light; the colon is a green light. The previous sentence illustrates the principle.

Now you've got it--Dr. Arn's remedy for all punctuation ills.

P.S.: Contrary to what you've been led to believe, there is absolutely nothing wrong with using either the dash (see the one in the previous sentence?) or parentheses (to separate off something that is truly parenthetical more forcefully and clearly than commas can). Learn to use both effectively and you will improve your sentence variety and intelligibility.

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Rev 1/11