Sentence formation is one of the key ingredients to grammar instruction in the early years of school. Students often start with simple sentences, and the urge to continue writing simple sentences in paragraphs and on short essays remains with the students as an “easy way” to make the grade. Instruction in compound and complex sentences early on in a child’s education can help to stop this trend before it starts and encourage sentences that are unique and full of meaning. Here are a few brief words on writing compound and complex sentences.
Before a student can even begin to write a compound or a complex sentence (at least intentionally), he or she must understand the form and function of the clause. A clause is any portion of a sentence that includes a subject and a verb. The word “clause” itself does not necessarily denote a complete sentence. Simple sentences are made of “independent clauses,” standalone sentences which include a subject and a verb phrase (or a predicate). An independent clause may simply read, “Erin loves her brother.” The subject, Erin, completes an action, loving. The sentence may be expanded by including a compound subject, as in “Erin and Kelly love their brother.” A compound verb may be added, to the original sentence, making it “Erin loves and respects her brother.” Nevertheless, we still have one clause—a complete thought, and a complete sentence. Clause formation is the first step in writing complex and compound sentences.
A compound sentence is a sentence that combines two independent clauses with the help of a coordinating conjunction. These conjunctions, often referred to by the mnemonic acronym FANBOYS, are for, and, nor, but, or, yet, and so. Coordinating conjunctions allow independent clauses to be connected to one another, allowing two different thoughts to be expressed together in the same sentence. For example, one might say, “Erin loves her brother, but her friends make fun of him.” This is a compound sentence. It essentially joins together two sentences: “Erin loves her brother,” and “Her friends make fun of him.” The coordinating conjunction “but” sets a condition or qualification in between the two sentences and expresses opposition. If, on the other hand, one were to combine “Erin loves her brother” with the sentence “Kelly adores him, too,” the conjunction “and” would be the most appropriate choice. Compound sentences combine two different subjects and two different verbs. Therefore, the mere presence of a preposition can be used to connote a variety of different ideas. “Michael played ball and his sister stayed home” is different from “Michael played ball, but his sister stayed home,” which suggests some sort of opposition. “Michael played ball, so his sister stayed home” suggests a direct relationship between the two.
All of the sentences above use independent clauses, which work just fine as sentences on their own. When an independent clause is joined with a dependent clause, one which cannot stand alone, one has created a complex sentence. There are a couple of things to remember when writing complex sentences. First, a subordinating conjunction (because, although, which) is used, and second, comma use is extremely important. In the instance of the sentence, “When he cried, Steven felt foolish,” we combine the dependent clause, the part of the sentence before the comma, with the independent “Steven is foolish,” a sentence in its own right. Notice that, because the subordinator comes first, a comma is necessary. If we were to write, “Steven cried after he saw the letter,” the subordinator comes second. It would be inappropriate to place a comma before the subordinator “after he saw the letter.” Complex sentences can sometimes combine multiple sentences into one without a single comma. One can take three sentences, “Steven cried. He felt terrible for what he had done. He fell on his knees,” and combine them into one simple sentence. “Steven, feeling terrible for what he had done, fell on his knees and cried” is a much more eloquent way of combining the first three subject-verb sentences into a coherent phrase.