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Grammar and Mechanics: Sentence Structures and Types of Sentences

Definitions and Examples of Basic Sentence Elements

The Mastering the Mechanics webinar series also describes required sentence elements and varying sentence types. Please see these archived webinars for more information.

 

Key: Yellow, bold = subject; green underline = verb; blue, italics = object; pink, regular font = prepositional phrase

 

Independent clause: An independent clause can stand alone as a sentence. It contains a subject and a verb and is a complete idea.

  • I used a phenomenological research design.
  • Participants described their perceptions.
  • Data obtained from the face-to-face interviews revealed participants’ lived experiences.

Dependent clause: A dependent clause (or subordinate clause) also contains a subject and a verb but is not a complete sentence by itself. It must be attached to an independent clause.

  • Because I used a phenomenological research design, . . .
  • When participants described their perceptions, . . .
  • . . . so that interviewees could verify the accuracy of my interpretations.

Subject: A person, animal, place, thing, or concept that does the action in the sentence. Determine the subject by asking the question Who or what? Notice that the subject is a noun phrase that may consist of a single word or a group of words.

  • I used a phenomenological research design.
  • Participants described their perceptions.
  • Data obtained from the face-to-face interviews revealed participants’ lived experiences.

Verb: Expresses what the person, animal, place, thing, or concept does. Determine the verb in a sentence by asking the question “What was the action or what happened?”

  • I used a phenomenological research design.
  • Participants described their perceptions.
  • Data obtained from the face-to-face interviews revealed participants’ lived experiences.
  • These findings are consistent with those of previous studies.

Note: The verb be sometimes acts as a copula or a linking verb, as in the last example above. It links the subject, in this case these findings to its complement, in this case, consistent with those of previous studies.)

Object: A person, animal, place, thing, or concept (noun phrase) that receives the action. Determine the object in a sentence by asking the question Who or what is being acted upon? 

  • I used a phenomenological research design.
  • Participants described their perceptions.
  • Data obtained from the face-to-face interviews revealed participants’ lived experiences.

Prepositional Phrase: A phrase consisting of a preposition (e.g., in, at, for, behind, until, after, of, during) and the word(s) following it (most often a noun phrase). A prepositional phrase can modify a noun, a verb, an adjective, or even an entire sentence. A prepositional phrase answers one of many questions, for example, Where? When? How? In what way?

  • For this study, I used a phenomenological research design.
  • Data obtained from the face-to-face interviews revealed participants’ lived experiences.
  • These findings are consistent with those of previous studies.

English Sentence Structure

  • A new sentence begins with a capital letter.
    • Smith reported similar results.
  • A sentence ends with punctuation (most often a period).
    • Smith reported similar results.
  • A sentence contains a subject that is only given once.
    • Smith he reported similar results.
  • A sentence contains a verb (often with a complement or modifier).
    • Smith reported similar results.
  • A sentence generally follows subject + verb + object word order.
    • Smith (subject) reported (verb) similar results (object).
  • A sentence must have a complete idea that stands alone. This is also called an independent clause.
    • Smith reported similar results.

Simple Sentences

simple sentence consists of only one independent clause: a subject and a verb, often with an object and modifiers.

Key: yellow, bold = subject; green underline = verb; blue, italics = object

Here are a few basic examples:

  • He read.
  • Employee turnover is expensive.
  • I employed a qualitative, multiple case study design.
  • I studied semistructured interviews.

Important note about simple sentences: The term simple refers to the clause structure of the sentence (i.e., one independent clause). However, researchers (e.g., Biber et al., 2011) have found, in academic English, that the noun phrases (subject and object) within a simple sentence are usually complex. In other words, in academic writing, a so-called simple sentence is still likely to be rich with information embedded in its noun phrases. Here are a few published examples of simple sentences with complex noun phrases from Biber et al. (2011):

  • Early research of this type considered mostly the writing of primary and secondary school students who were native speakers of English (e.g., Anderson, 1937; Frogner, 1933; LaBrant, 1933).
     
  • The vast majority of these studies have relied on the construct of the T-unit: a main clause and all associated dependent clauses.
     
  • The continuing reliance on these measures to assess writing development reflects traditional notions of complexity and the widespread belief that academic written discourse is complex in that it relies heavily on elaborated structures.

Taking just the main word of the subject, verb, and object from the above examples shows how much valuable information has been packed into the noun phrases:

  • research considered writing
  • majority relied on construct
  • reliance reflects notions and belief

 

Reference

Biber, D., Gray, B., & Poonpon, K. (2011). Should we use characteristics of conversation to measure grammatical complexity in L2 writing development? TESOL Quarterly, 45(1), 5–35. https://doi.org/10.5054/tq.2011.244483

Compound Sentences

compound sentence contains at least two independent clauses. These two independent clauses can be combined using a comma with a coordinating conjunction or using a semicolon.

Key: independent clause = yellow, boldcomma or semicolon = pink, regular font; coordinating conjunction = green, underlined

Here are a few examples:

  • Employee turnover is expensive, so it is necessary to explore strategies managers use to maintain a low rate of turnover.
  • I employed a qualitative, multiple case study design, and I analyzed data from a variety of sources.
  • I conducted semistructured interviews; then, I used NVivo software to transcribe the interviews word for word.

Using some compound sentences in writing allows for more sentence variety.

Complex Sentences

complex sentence contains at least one independent clause and at least one dependent clause. Dependent clauses can refer to the subject (who, which) the sequence/time (since, while), or the causal elements (because, if) of the independent clause.

Key: yellow, bold = independent clause; pink, regular font = comma; blue, italics = dependent clause

Here are a few examples:

  • Because employee turnover is expensive, it is necessary to explore strategies managers use to maintain a low rate of turnover.
  • Even though I conducted semistructured interviews with managers, I also used other company documents to help answer my research questions.
    • Note that a comma is used in the first two examples because the sentences begin with the dependent clause.
  • I employed a qualitative, multiple case study design as I analyzed data from a variety of sources.
    • Note that no comma is used when the sentence begins with an independent clause.

Using some complex sentences in writing allows for more sentence variety.

Compound-Complex Sentences

Sentence types can also be combined. A compound-complex sentence contains at least two independent clauses and at least one dependent clause.

Key: yellow, bold = independent clause; pink, regular font = comma or semicolon; green, underlined = coordinating conjunction; blue, italics = dependent clause

  • Because employee turnover is expensive, I explored strategies managers use to maintain a low rate of turnover, and I discovered four themes.
  • Although I considered qualitative, quantitative, and mixed-methods approaches, I settled on a qualitative, multiple case study design; this design allowed me to analyze data from a variety of sources to answer the research question.
  • I conducted interviews with managers, and I reached saturation after nine interviews even though I had originally scheduled 12 interviews.

Pay close attention to comma usage in complex-compound sentences so that the reader is easily able to follow the intended meaning.

Using some compound-complex sentences in writing allows for more sentence variety.