Kinds of Sentences

Kinds of Sentences

There are three kinds of sentences.
Simple sentences
Complex sentences
Compound sentences

Simple Sentences

A simple sentence is a sentence that consists of just one independent clause. A simple sentence has no dependent clauses. (An independent clause (unlike a dependent clause) can stand alone as a sentence.)

I cannot drink warm milk.
A day without sunshine is like night.
Only the mediocre are always at their best. (Novelist Jean Giraudoux)
Reality continues to ruin my life. (Cartoonist Bill Watterson)

A simple sentence is not always a short, basic sentence like the four examples shown above. A simple sentence could have a compound subject (i.e., a subject with two or more simple subjects). For example:

Jack likes walking.

(This is a simple sentence with one simple subject ("Jack").)

Jack and Jill like walking.

(This is a simple sentence with a compound subject made up of two simple subjects ("Jack" and "Jill").)

A simple sentence could also have a compound predicate (when two or more verbs share the same subject). For example:

Jack likes fishing.

(This is a simple sentence with a normal predicate, i.e., there's just one main verb ("likes").)

Jack likes fishing but hates hunting.

(This is a simple sentence with a compound predicate. The subject "Jack" is the subject of two verbs ("likes" and "hates").)

Jack likes walking and fishing but hates running and hunting.

(This is still a simple sentence with a compound predicate. The subject "Jack" is still the subject of two verbs ("likes" and "hates"), but you can see how a simple sentence could start to get quite busy.)

Here's an example of a simple sentence with a compound subject, a compound predicate, and direct objects with more than one item.

Jack and Jill like walking and fishing but hate running and hunting.

(This is still a simple sentence. There are no dependent clauses.)

Be clear on when to use a comma before "and."

Being able to identify a simple sentence helps with comma placement. Writers are often unsure when to use a comma before words like "and," "or," and "but" (called conjunctions).

Let's look at some examples:

Jack likes chicken and loves Nando's.
Jack likes chicken but hates turkey.

(These are both examples of simple sentences with compound predicates. In each example, there is one subject governing two verbs. Note that there is no comma before the "and" or the "but.")

Compare the two examples above with these sentences:

Jack likes chicken, and he loves Nando's.
Jack likes chicken, but he hates turkey.

(These look similar, but they are not simple sentences with compound predicates. There are two subjects ("Jack" and "he"), each governing its own verb. These are examples of compound sentences not simple sentences with compound predicates. Each sentence features two independent clauses, not one. Note that there is now a comma before the "and" and the "but.")

The Rule
Use a comma before an "and" (or "but," "or," etc.) that joins two independent clauses (i.e., clauses that could stand alone as sentences).

Remember that with a compound predicate, the second half of the predicate cannot stand alone as a sentence because it doesn't have its own subject.

Jack likes chicken and loves Nando's.

(In this example of a simple sentence, "loves Nando's" is not an independent clause. That's why there's no comma before "and.")

Jack likes chicken, and he loves Nando's.

(In this example of a compound sentence, "he loves Nando's" is an independent clause. That's why there is a comma before "and.")

Key Point

When a simple sentence has compound predicate, don't separate the subject from its second verb with a comma.

My dog likes toast, but does not eat bread.
My dog likes toast but does not eat bread.

Complex Sentences

A complex sentence has one independent clause and at least one dependent clause.

Stay in the bath until the phone rings.
Both the cockroach and the bird would get along very well without us, although the cockroach would miss us most. (Joseph Wood Krutch, 1893-1970)
Leave while you can.
When a distinguished but elderly scientist states that something is possible, he is almost certainly right. When he states that something is impossible, he is very probably wrong. (Arthur C. Clarke)

(This is two complex sentences.)

Subordinating Conjunctions in Complex Sentences

The word used to link an independent clause to a dependent clause is called a subordinating conjunction.

The most common subordinating conjunctions are although, because, before, even though, if, since, until, and when.

In these examples of complex sentences, the subordinating conjunctions are shown in bold.

We can never obtain peace in the outer world until we make peace with ourselves. (Dalai Lama)
Wise men speak because they have something to say. Fools speak because they have to say something. (Athenian philosopher Plato)
Even though he's a moron, I supported Tyson Fury. (Boxer David Haye)

The role of a subordinating conjunction and the dependent clause is to establish a time, a place, a reason, a condition, a concession, or a comparison for the main clause. (NB: Dependent clauses are also known as a subordinate clauses.)

Read more about subordinating conjunctions.

(Issue 1)Use a comma after a fronted adverbial.

Learning how to spot a complex sentence is useful because it helps with punctuating sentences correctly. In particular, it helps with deciding whether to use a comma with the dependent clause.

When your dependent clause is at the front and acts like an adverb – typically stating a time (e.g., When it's ready), a place (e.g., Where they live), or a condition (e.g., If you were in my shoes) – then it is usual to use a comma after the dependent clause to show where the independent clause starts. When such a clause appears at the back of your sentence, it is usually not offset with a comma. In these examples, the independent clauses are shaded.

I became a people-watcher when I lost all my friends. (Singer Taylor Swift)
When I lost all my friends, I became a people-watcher.

If it is, it is. If it's not, it's not. (Singer Ziggy Marley)
It is if it is. It's not if it's not.

So, the guidance is as follows:

When your adverbial is at the front, use a comma.
Don't use a comma when your adverbial is at the back.

(Issue 2)Unfortunately, there is a little more to Issue 1 than stated. The comma really determines whether the clause is restrictive or non-restrictive. However, the simple rule given at Issue 1 will satisfy 99% of situations.

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.

I like coffee. Mary likes tea. → I like coffee, and Mary likes tea.
Mary went to work. John went to the party. I went home. → Mary went to work, but John went to the party, and I went home.
Our car broke down. We came last. → Our car broke down; we came last.

Joining Compound Sentences with Coordinating Conjunctions

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

The term coordinating conjunction sounds complicated, but in fact there are only seven of them and they are all short, one-syllable words: For—And—Nor—But—Or—Yet—So — 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).

and

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

We use and to join two clauses that have equal value, for example: London is in England, and Rome is in Italy.
We use and to join two clauses when the second clause happens after the first clause, for example: There was a big bang and the lights went out.
We use and to join two clauses when the second clause is a result of the first clause, for example: He went to bed early, and the next day he felt better.

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.
- He's already had three beers and now wants another one.
You can take a train, or you can take a bus.
- You can take a train or take a bus.

Joining Compound Sentences with Semicolons

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

He studied very little; he failed his exams.
The sky is cloudy; it's going to rain.
Ram cut the grass; Ati trimmed the hedge; Tara watched.

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 (,).

Look at these examples:

John loves Mary; however, Mary doesn't love John.
Salad is not expensive; moreover, it's very healthy.
What he did was incredible; in fact, I can hardly believe it.

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.
~~John drank coffee, Mary drank tea.~~
John drank coffee, and Mary drank tea.
John drank coffee, but Mary drank tea.
John drank coffee; Mary drank tea.

Compound Sentence Examples

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

Compound Sentences with Coordinating Conjunctions

The cinema was sold out, so we watched a movie on TV.
I'll have a week in Rome, or I'll go to Paris for three days.
I really need a holiday, but I don't have the money, and I don't have the time.
He's crazy! He doesn't like the car, yet he bought it anyway.
It's gone 10pm, and he still hasn't arrived.
Our car broke down, so we took a taxi.
Our plane left Bangkok on schedule, and we arrived in London early.
I cannot criticize him, for he is my brother.
There are no eggs in the fridge, nor is there any bread in the cupboard.
I would have passed the exam, but I didn't study enough.
Should they take the test now, or should they wait until next month?
I have never visited Moscow, nor have I been to St Petersburg.
The pain was really bad, yet he refused to see a doctor.

Compound Sentences with Semicolons

The Angel Falls waterfall in Venezuela plunges 907 metres; it looks spectacular.
The entire town was flooded; people used boats.
We always shop at the supermarket; it's got everything in one place.
Call us next week; it should be in then.
You can pay online; we accept all major credit cards.
I only write non-fiction; I've never tried fiction.

Compound Sentences with Conjunctive Adverbs

Frantic is my favourite film; however, I've only seen it once.
He turned himself in to the police; otherwise, they would have arrested him.
He's got a really good job; at least, that's what he says.
He claimed he was working last night; however, nobody saw him at the office.

Compound Sentences in Famous Quotations

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

"Age shall not weary them, nor the years condemn." Laurence Binyon
"To be uncertain is uncomfortable; but to be certain is ridiculous." Goethe
"For dust thou art, and unto dust shalt though return." Bible
"Some cause happiness wherever they go; others, whenever they go." Oscar Wilde
"The girl was beheaded, chopped into pieces and placed in a trunk, but was not interfered with." British newspaper report
"I am just going outside and may be some time." Captain Lawrence Oates
"I desire to go to Hell and not to Heaven." Niccolo Machiavelli
"Power tends to corrupt and absolute power corrupts absolutely." Lord Acton
"Don't confuse fame with success. Madonna is one; Helen Keller is the other." Erma Bombeck

Compound Sentences in Sayings

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

Give a thief enough rope and he'll hang himself.
There's one law for the rich, and another for the poor.
A man is as old as he feels, and a woman is as old as she looks.
Money is a good servant, but a bad master.
Talk of the Devil, and he is bound to appear.
There is a time to speak and a time to be silent.
You can lead a horse to water, but you can't make it drink.