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English Writing: Punctuation (the Comma, p. 2), Essential vs. Nonessential Use
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Overview
This video explains the difference between essential and non-essential clauses and phrases in English writing, focusing on how commas are used (or not used) to set them apart. Essential elements are crucial for the sentence's meaning and are not set off by commas, while non-essential elements provide extra information and are enclosed in commas. The video covers adjective clauses and phrases, adverb clauses, and noun clauses, illustrating these concepts with numerous examples to help viewers improve their punctuation accuracy and clarity.
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Chapters
- Essential information is necessary to identify or define the noun or concept it modifies; it cannot be removed without changing the core meaning of the sentence.
- Non-essential information provides additional, descriptive details that can be removed without altering the fundamental meaning of the sentence.
- Essential elements are integrated directly into the sentence without commas.
- Non-essential elements are set apart by commas, indicating they are parenthetical or supplementary.
Understanding this distinction is crucial for clear communication, as incorrectly placed commas can alter the intended meaning of a sentence or confuse the reader.
Essential: 'The man who lives next door is a doctor.' (identifies which man). Non-essential: 'Dr. Brown, who lives next door, is moving to Chicago.' (extra info about Dr. Brown).
- Essential adjective clauses, often introduced by 'that,' are not set off by commas because they are necessary for identification.
- Non-essential adjective clauses, often introduced by 'which,' are set off by commas because they provide extra, non-defining information.
- When adjective clauses are reduced to participial phrases (e.g., 'proposed' instead of 'that were proposed'), the comma usage follows the same essential/non-essential rule.
- Relative pronouns like 'who,' 'whom,' 'whose,' and 'which' signal adjective clauses, and their use with or without commas depends on whether the clause is essential or non-essential.
Correctly punctuating adjective clauses prevents ambiguity and ensures that the reader understands which specific person, place, or thing is being discussed.
Essential: 'The solutions that were proposed are being reviewed.' (identifies specific solutions). Non-essential: 'The solutions, which range from the absurd to the miraculous, are being reviewed.' (adds description to already identified solutions).
- An essential adjective clause introduced by 'that' can sometimes be interrupted by other phrases or clauses, requiring commas around the interruption, not around the 'that' clause itself.
- When a preposition is used with a relative pronoun (e.g., 'about which,' 'of whom'), the clause is typically non-essential and requires commas.
- Noun clauses, which function as nouns and often start with 'that,' are essential to the sentence's structure and are never set off by commas.
Recognizing interruptions and the function of prepositional and noun clauses helps maintain sentence integrity and avoids misinterpreting the relationships between different parts of the sentence.
Interrupted essential clause: 'Any country, whether it is a treaty member or not, may submit a request.' Noun clause: 'They who vandalized it were caught.' (no commas around 'who vandalized it' because it's essential).
- Adverb clauses modify verbs, adjectives, or other adverbs and indicate time, place, manner, condition, etc.
- When an adverb clause begins a sentence, it is followed by a comma.
- When an adverb clause is placed in the middle of a sentence, it is set off by commas.
- Adverb clauses at the end of a sentence generally do not require a comma unless they are non-essential or add a distinct afterthought.
Properly punctuating adverb clauses clarifies the relationship between the action or state described in the main clause and the circumstances described in the adverb clause.
Beginning adverb clause: 'If a stock market investor fails to properly research companies, he is almost certain to fail.' Middle adverb clause: 'The investor, if he wants to succeed, must research companies.' End adverb clause: 'He is almost certain to fail if he does not research companies.'
- Adjective phrases (like prepositional phrases or participial phrases) function similarly to adjective clauses: essential ones are not set off by commas, while non-essential ones are.
- Appositives are nouns or noun phrases that rename or explain another noun right beside it; they are set off by commas if they are non-essential.
- When a noun has multiple attributes, the writer must decide if the attribute is essential for identification (no comma) or non-essential description (commas).
Using commas correctly with phrases and appositives ensures that the reader can distinguish between identifying information and additional descriptive details.
Essential phrase: 'The company with the lowest bid will be given the contract.' Non-essential appositive: 'Fitzgerald's debut novel, 'This Side of Paradise,' is not widely known.'
Key takeaways
- The core difference between essential and non-essential elements lies in whether they are required for the sentence's basic meaning.
- Commas signal that information is supplementary or non-essential, allowing the reader to omit it without losing the sentence's primary message.
- Adjective clauses starting with 'that' are typically essential and do not use commas, while those starting with 'which' are usually non-essential and require commas.
- Reduced adjective clauses (participial phrases) follow the same essential/non-essential comma rules.
- Noun clauses, functioning as the subject or object, are always essential and never take commas.
- Adverb clauses require commas when they begin or interrupt a sentence, but often not when they end it.
- Pay close attention to comma usage, as it significantly impacts sentence clarity and meaning.
Key terms
Essential clause/phraseNon-essential clause/phraseAdjective clauseAdverb clauseNoun clauseRelative pronounParticipial phraseAppositiveRestrictive clauseNon-restrictive clause
Test your understanding
- What is the primary function of an essential clause in a sentence?
- How does the use of commas differentiate between essential and non-essential information?
- Why are noun clauses never set off by commas?
- What is the rule for using commas with adjective clauses introduced by 'that' versus 'which'?
- How can you determine if a phrase modifying a noun is essential or non-essential?