10 Grammar Rules Every Teacher Should Know

Rule #2 Understand Parts of Sentences
Sentences, too, have parts: subjects, predicates, clauses and objects. These, too, are related to functions:

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  The subject is the primary “noun” segment of the sentence. It tells us what is being discussed.
  
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  The predicate is the primary “verb” segment. It tells us what the subject is doing.
  
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  Objects are nouns other than the subject which are acted upon by verbs or prepositions. They tell us what is being affected by the subject and verb.
  
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  Clauses are sentence fragments included to expand the meaning of the sentence. (Prepositional phrases are a kind of short clause.) They tell us something about the subject or verb that is indirectly related to what’s happening in the sentence.
  

A sentence must have at least a subject and predicate to be complete; objects and clauses are additional levels of complexity. Keeping our image in mind, here are examples:

Subject Predicate

The red car moves.

Subject Predicate with Object

The quick red car hits a huge pothole.

Subject Predicate with Prepositional Phrase

The red car moves quickly on the road.

Clause with Prepositional Phrase Subject Predicate with Object and Prepositional Phrase

Moving quickly on the road, the red car hits a huge pothole by the curb.

Recognizing the parts of a sentence helps us to identify common writing problems like sentence fragments (a sentence is missing either a subject or predicate) and run-on sentences (a sentence with too many subjects and predicates). When you want to analyze a sentence, first break it down into the subject and predicate, then look at other elements (clauses and objects) to see if they add or detract from the meaning. Remove any parts that are superfluous or confusing—this is the key to clear writing.