Identifying the Word Class of 'therefore'

The question asks us to determine the word class, also known as the part of speech, of the underlined word "therefore" in the sentence: "My sister is just sixteen and therefore not eligible to vote." To answer this, we need to understand how "therefore" functions within this sentence and recall the definitions of the word classes provided in the options.

Analyzing the Sentence and the Word 'therefore'

The sentence presents two ideas: "My sister is just sixteen" and "not eligible to vote". The word "therefore" connects these two ideas, showing a cause-and-effect or reason-result relationship. Because she is sixteen, she is not eligible to vote.

"Therefore" indicates a consequence or result that follows from the previous statement. Let's look at how it modifies the rest of the sentence.

Understanding Word Classes (Parts of Speech)

Let's quickly review the word classes given in the options:

• Gerund: A form of a verb, ending in -ing, that is used as a noun (e.g., swimming is fun).
• Adverb: A word or phrase that modifies or qualifies an adjective, verb, or other adverb or a word group, expressing a relation of place, time, circumstance, manner, cause, degree, etc. (e.g., quickly, here, yesterday, very). Some adverbs, like conjunctive adverbs, connect independent clauses and show relationships between them (e.g., however, moreover, therefore).
• Adjective: A word that describes or modifies a noun or pronoun (e.g., happy, large, blue).
• Conjunction: A word used to connect clauses or sentences or to coordinate words in the same clause (e.g., and, but, because, or).

Determining the Word Class of 'therefore'

In the sentence, "therefore" is used to show the result of her age (sixteen). It indicates *why* she is not eligible to vote. It modifies the statement "not eligible to vote" by explaining the circumstance or reason. This function fits the definition of an adverb.

Specifically, "therefore" is often classified as a conjunctive adverb. Conjunctive adverbs connect independent clauses and indicate a logical relationship between them, such as cause and effect (therefore, consequently), contrast (however, nevertheless), or addition (moreover, furthermore).

While "therefore" helps connect the ideas like a conjunction, its primary role is adverbial – it modifies the second part of the sentence by providing the reason based on the first part. It acts as a transition word that shows a resultant relationship.

Evaluating the Options

• Gerund: Incorrect. "Therefore" does not end in -ing and is not used as a noun.
• Adverb: Correct. "Therefore" functions as a conjunctive adverb, modifying the clause "not eligible to vote" by indicating the reason or consequence derived from the first part of the sentence.
• Adjective: Incorrect. "Therefore" does not describe a noun or pronoun.
• Conjunction: Incorrect (in this specific classification context). While it connects ideas, its function as showing consequence is adverbial. Simple conjunctions like 'and' join clauses without adding this specific adverbial meaning of result.

Therefore, the word class of "therefore" in the given sentence is Adverb.

Revision Table: Key Word Classes

Additional Information on Conjunctive Adverbs

Conjunctive adverbs like "therefore," "however," "moreover," "consequently," "furthermore," etc., are important for showing relationships between independent clauses. When connecting two independent clauses, they are typically preceded by a semicolon and followed by a comma:

Example: She studied hard; therefore, she passed the exam.

In the given sentence, "and therefore" is used. Here, "and" is the coordinating conjunction connecting "My sister is just sixteen" (an independent clause) and "therefore not eligible to vote" (which can be seen as a shortened clause or a phrase modified adverbially). Even in this structure, "therefore" retains its adverbial function of indicating result.