The Structure of a Sentence
Remember that every clause is, in a sense, a miniature sentence. A simple sentences contains only a single clause, while a compound sentence, a complex sentence, or a compound-complex sentence contains at least two clauses.
I drink coffee
I drink coffee is an independent clause. It contains a Subject (I) and a Verb (drink), and it expresses a complete thought.
The most basic type of sentence is the simple sentence, which contains only one clause. A simple sentence can be as short as one word:
Usually, however, the sentence has a subject as well as apredicate and both the subject and the predicate may havemodifiers. All of the following are simple sentences, because each contains only one clause:
The ice melts quickly.
The ice on the river melts quickly under the warm March sun.
Lying exposed without its blanket of snow, the ice on the river melts quickly under the warm March sun.
As you can see, a simple sentence can be quite long -- it is a mistake to think that you can tell a simple sentence from a compound sentence or a complex sentence simply by its length.
The most natural sentence structure is the simple sentence: it is the first kind which children learn to speak, and it remains by far the most common sentence in the spoken language of people of all ages. In written work, simple sentences can be very effective for grabbing a reader's attention or for summing up an argument, but you have to use them with care: too many simple sentences can make your writing seem childish.
When you do use simple sentences, you should add transitional phrases to connect them to the surrounding sentences.
A compound sentence consists of two or more independent clauses (or simple sentences) joined by co-ordinating conjunctions like "and," "but," and "or":
Canada is a rich country.
Still, it has many poor people.
Canada is a rich country, but still it has many poor people.
Compound sentences are very natural for English speakers -- small children learn to use them early on to connect their ideas and to avoid pausing (and allowing an adult to interrupt):
Today at school Mr. Moore brought in his pet rabbit, and he showed it to the class, and I got to pet it, and Kate held it, and we coloured pictures of it, and it ate part of my carrot at lunch, and ...
Of course, this is an extreme example, but if you over-use compound sentences in written work, your writing might seem immature.
A compound sentence is most effective when you use it to create a sense of balance or contrast between two (or more) equally-important pieces of information:
Montéal has better clubs, but Toronto has better cinemas.
There are two special types of compound sentences which you might want to note. First, rather than joining two simple sentences together, a co-ordinating conjunction sometimes joins two complex sentences, or one simple sentence and one complex sentence. In this case, the sentence is called a compound-complex sentence:
The package arrived in the morning, but the courier left before I could check the contents.
The second special case involves punctuation. It is possible to join two originally separate sentences into a compound sentence using a semicolon instead of a co-ordinating conjunction:
Sir John A. Macdonald had a serious drinking problem;when sober, however, he could be a formidable foe in the House of Commons.
Usually, a conjunctive adverb like "however" or "consequently" will appear near the beginning of the second part, but it is not required:
The sun rises in the east; it sets in the west.
A complex sentence contains one independent clause and at least one dependent clause. Unlike a compound sentence, however, a complex sentence contains clauses which are notequal. Consider the following examples:
My friend invited me to a party. I do not want to go.
My friend invited me to a party, but I do not want to go.
Although my friend invited me to a party, I do not want to go.
In the first example, there are two separate simple sentences: "My friend invited me to a party" and "I do not want to go." The second example joins them together into a single sentence with the co-ordinating conjunction "but," but both parts could still stand as independent sentences -- they are entirely equal, and the reader cannot tell which is most important. In the third example, however, the sentence has changed quite a bit: the first clause, "Although my friend invited me to a party," has become incomplete, or a dependent clause.
A complex sentence is very different from a simple sentence or a compound sentence because it makes clear which ideas are most important. When you write
My friend invited me to a party. I do not want to go.
My friend invited me to a party, but I do not want to go.
The reader will have trouble knowing which piece of information is most important to you. When you write the subordinating conjunction "although" at the beginning of the first clause, however, you make it clear that the fact that your friend invited you is less important than, or subordinate, to the fact that you do not want to go.
The English language provides considerable flexibility in sentence construction. Using various sentence patterns produces speech and writing that are lively and interesting. Also, variety in sentence construction contributes to well-organized messages.
1) SIMPLE SENTENCE
The simple sentence is an independent clause without subordinate clause. It begins with a capital letter and closes with an end mark. Simple sentences can vary considerably in length.
- I bought four apples at the farmers’ market.
- I bought four apples, a basket of tomatoes, a bag of green beans, and three squashes at the farmers’ market.
- The farmers’ market is a classic example of producers selling directly to consumers and avoiding the attempts of agents to control the supply or to manipulate the price.
2) COMPOUND SENTENCE
The compound sentence contains two or more independent clauses but no subordinate clauses. The two independent clauses are joined by a comma (,) followed by a conjunction (for, and, nor, but…). They may also be joined by a semicolon (;), a semicolon followed by a linking adverb (therefore, however, because, since…), or a colon (:).
- I don’t know where he went, and no one has seen him since this afternoon. (conjunction)
- Harold the First fought in northern Ireland; his campaigns generally were successful. (semicolon)
- Vivian wanted to stay another week in Ashville; however, her parents refused to send her more money. (linking adverb)
- You must have heard the news: we’re all getting bonuses this year! (colon)
a) Compound Sentences with Coordinators
Independent Clause + , + Coordinators + Independent Clause
The two independent clauses are joined by a comma and one of the seven coordinating conjunctions: for, and, nor, but, or, yet, and so. You can remember the coordinating conjunctions by remembering the word FANBOYS. The following sentences illustrate their meanings.
1. The Japanese have the longest life expectancy of any other people, for their diet is extremely healthful. (for expresses reason)
2. The Japanese consume a lot of rice, and they eat more fish than red meat. (and expresses equal related ideas)
3. Many Americans, on the other hand, do not eat a healthy diet, nor do they get enough exercise. (nor joins two equal negative independent clauses)
4. In the last twenty years, Americans have reduced their smoking, but Europeans seem to be smoking more than ever. (but expresses contrasting ideas)
5. Europeans should change their smoking habits, or they will risk developing lung cancer. (or expresses alternatives or possibilities)
6. Many Japanese men smoke, yet the Japanese have long life expectancies. (yet expresses an unexpected contrast)
7. The Japanese diet is becoming more westernized, so their life expectancy will probably decrease in the future. (so expresses results)
b) Compound Sentences with Linking Adverbs (Conjunctive Adverbs)
Independent Clause; + Conjunctive Adverb, + Independent Clause
The two independent clauses are joined by a semicolon (;), a conjunctive adverb and a comma. Just like the FANBOYS coordinators, conjunctive adverbs express the relationship of the second clause to the first clause. The chart below shows the coordinators and conjunctive adverbs which express similar relationship.
Furthermore, besides, moreover, also
However, nonetheless, nevertheless, still
Consequently, thus, therefore, hence, accordingly
- Junior colleges offer preparation for the professions, business, and industry; moreover, they prepare students to transfer to a four-year college or university. (equal related ideas)
- Many junior colleges do not provide dormitories; however, they provide housing referral services. (opposite ideas)
- Students must take the final exam; otherwise, they will receive a grade of Incomplete. (“or else”)
- Native and non-native English speakers have different needs; therefore, most schools provide separate English classes for each group. (results)
c) Compound Sentences with Semicolon
Independent Clause + ; + Independent Clause
The two independent clauses are joined by a semicolon (;). Use a semicolon only when the two independent clauses are closely related and the relationship is implied.
- My older brother studies laws; my younger brother studies medicine.
- The Berlin Wall’s construction in 1961 surprised the world; its destruction in 1989 stunned it.
- Poland was the first Eastern block country to turn away from communism; others soon followed.
3) COMPLEX SENTENCES
A complex sentence contains one independent clause and one or more dependent clause. In a complex sentence, one idea is generally more important than the other one. The more important idea is placed in the independent clause, and the less important idea is placed in the dependent clause.
Independent Clause + Dependent Clause
Dependent Clause + , + Independent Clause
In the following sentences, the independent clause is underlined, and the dependent clause is in italics.
- If you are not good at figures, it is pointless to apply for a job in a bank.
- When he saw the door open, the stranger entered the house.
- Holiday resorts which are very crowded are not very pleasant.
- That the Earth’s temperature is rising concerns scientists.
NOTE: There are three kinds of dependent clauses used in complex sentences: adverb, adjective and noun.
a- A dependent adverb clause begins with an adverbial subordinator such as when, while, because, even though, so that, etc.
b- A dependent adjective clause begins with a relative pronoun such aswho, whom, which, whose, or a relative adverb where, when, and why.
c- A dependent noun clause begins with that, a wh-question word, whether,and if.
4) COMPOUND-COMPLEX SENTENCES
A compound-complex sentence is a combination of two or more independent clauses and one or more dependent clauses. It is like a family of two adults and one or more children.
- After I finished high school, I wanted to go to university, but I had to work in my family’s business.
- The word root multi, which means many, comes from Latin, and the word root poly, which also means many, comes from Greek.
- When the power line snapped, Jack was listening to the radio, and Linda was reading in bed.
MODIFIERS IN SENTENCES
A modifier is any word or group of words which limits or qualifies the meaning of other parts of the sentence. Be sure that your modifiers are clearly joined to the word or words they qualify. Descriptive phrases or clauses joined to the wrong words are known as dangling modifiers.
You can correct dangling modifiers by making the doer of the action the subject of the sentence, by adding omitted words, or by changing the phrase to a subordinate clause.
- Coming over the hill, the blueberries were seen. (incorrect)
- Coming over the hill, we saw the blueberries in the valley below us. (correct)
- Referring to your request of April 12, the matter is being reviewed by our board. (incorrect)
- Our board is reviewing your request of April 12 for an additional 122 tons of steel. (correct)
- When she was four years old, her mother died. (incorrect)
- She was four years old when her mother died. (correct)
- Exhausted and bleary-eyed, the report was finished by the team in the morning. (incorrect)
- The team, exhausted and bleary-eyed, finished the report in the morning.