A photograph of a labeled jar, with a stack of other labels nearby

Source: Labels, Anne, Flickr

You can label sentences in many ways. You can label them for the number of words they contain. You can label them as sentences that start with the subject or sentences that start with an introductory phrase or clause. You can label them according to the number of syllables they contain. All these ways of labeling could give you information about your sentence variety and a direction for revision.

In this lesson, you will be concerned with the variety of sentence structures. By “sentence structure,” we mean the basic ways sentences are constructed as follows:

Simple sentences
Compound sentences
Complex sentences
Compound-complex sentences

Your objective in this lesson is to revise for sentence variety. However, this doesn’t mean having an equal number of sentences of each type. Your primary concern is to avoid having a predominant number of simple sentences. Therefore, in this lesson, your labeling will not distinguish between compound sentences, complex sentences, or compound-complex sentences. It will only distinguish between simple sentences and “non-simple” sentences.

Being able to identify compound, complex, and compound-complex sentences will still be important in this lesson, though. You will need to identify these sentence types as “non-simple” sentences. This is not always easy, especially when you come across sentences with compound subjects and/or compound predicates.

(For further review on this topic, check out Strengthen Sentence Variety/Sentence Combining and Using a Variety of Correctly Structured Sentences – Compound, Compound Complex in the Related Resources.)

An image of a diagram of a compound sentence

Source: *Compound Sentence, Steven Pavlov, Wikimedia

Compound Sentences and Compound Parts

Read these two sentences and click on the one you think is a simple sentence.

1.The women and the men and even the children brought pies, served ice cream, and cleaned up.

Correct! All the men, women, and children did all of the actions listed (brought pies, served ice cream, and cleaned up). The subjects are clustered together, and the verbs are clustered together into one compound subject and one compound predicate—in other words, a simple sentence. (Note: Having a compound subject or a compound predicate doesn’t make a sentence compound.)

2. The women brought pies, the men served ice cream, and the children cleaned up.

Try again. This sentence means that only women brought pies, only men served ice cream and only children cleaned up, and each subject has a verb assigned to it. This is a compound sentence, a sentence made of two or more complete sentences (independent clauses) joined by a coordinating conjunction.

Try the next two sentences. Identify each as either a simple sentence (may contain compound subjects or verbs) or a compound sentence (two or more complete sentences joined by a comma and a conjunction). Click on your response.

Grammar Talk: Let’s pause to consider the clause. A clause is a group of words that has a subject (singular or compound) and a predicate (singular or compound). A simple sentence has one clause. Since the clause in a simple sentence can stand by itself, it is called an independent clause.

Complex Sentences

A photograph of two slices of pie, most likely pumpkin and lemon

Source: Pie, Pie, Me oh My, I love Pie!, Alyss, Flickr

A photograph of a piece of iced, chocolate cake

Source: Cake!, Jill Siegrist, Flickr

It may seem like some of the sentences you have already looked at are complicated. Certainly you have seen long sentences and sentences with several parts clustered together.

A compound sentence and a complex sentence appear below. Read them, and then click on the one you think is a compound sentence.

1. Cakes are appropriate only on certain occasions, but any time is the right time for pie.

Correct! Two complete (independent) clauses are joined by the coordinating conjunction “but” to make a compound sentence. A comma comes before the conjunction.

2. Although cakes are appropriate only on certain occasions, any time is the right time for pie.

Try again. In this sentence, the clauses are joined by “subordinating” one clause, making it dependent on the other clause. The dependent clause begins with a subordinate conjunction. The two clauses are connected with a comma.

photo of the two industrial iron hooks that connect two train cars

Source: Train coupling, Daniel Schwen, Wikimedia Commons

Notice that if you move the independent clause (everything preceding the comma) to the end, the sentence doesn’t work. You end up with “But any time is the right time for pie, cakes are appropriate only on certain occasions.” So, the clauses cannot be reversed. Also, notice that a comma and a coordinating conjunction connect the two independent clauses, similar to two train cars being connected with a coupler.

photo of an old Southern Pacific semitrailer sitting in a train yard

Source: Faded Glory, Beedle Um Bum, Flickr

On the other hand, the subordinating conjunction “Although” is part of a dependent clause from the very start. This is like a semitrailer being loaded onto a flatbed train car: The semitrailer becomes a part of the train car. You will notice that the two clauses of the complex sentence can be reversed. If we reverse them, we end up with “Any time is the right time for pie, although cakes are appropriate only on certain occasions.”

Grammar Talk: One way to test whether a sentence part is a subordinate clause is to see if it can be changed to a different position in the sentence.

Read the three sentences below. Identify each as one of the following:

A simple sentence (may contain compound subjects or verbs)
A compound sentence (two or more sentences joined by a comma and a coordinating conjunction)
A complex sentence (an independent clause and at least one dependent clause joined by a subordinating conjunction)

Compound-Complex Sentences

Now we are going to get fancy and try to put two complex sentences together with a coordinating conjunction (and, or, but, etc.) to make a compound-complex sentence (two or more independent clauses with at least one dependent clause). In this case, the compound-complex sentence will contain more than the required number of dependent clauses.

Read the sentences below and click on the one that you think is a compound-complex sentence.

1. Pies are usually sweetened with sugar but can also be sweetened with molasses, honey, or maple syrup.

Try again.

2. Pies need to be sweetened with sugar, honey, maple syrup, or some other form of sweetener.

Try again.

3. Although fruit pies may seem less sweet than cakes, pies do not necessarily have less sugar than cakes, but they have the added nutritional value of the fruit.

Correct! This sentence begins with a dependent clause and subordinating conjunction: “Although fruit pies may seem less sweet than cakes” and contains two independent clauses that can stand on their own as sentences: “pies do not necessarily have less sugar than cakes,” and “they have the added nutritional value of the fruit.”

Read the sentences below and choose simple sentence or non-simple sentence for each one.