Analyzing the Blank in the Passage

The question asks us to fill in a blank in a passage to make it grammatically correct and meaningful. The passage talks about siblings who sing and notes that one of them has less vocal prowess than others, even if their potential is similar.

Let's look at the sentence containing the blank:

"It so happens that ______ siblings sing, one of ______ invariably has a less ______ vocal prowess even though ______ have a similarly commendable ______ base."

We are specifically looking at the second blank:

"...one of ______ invariably has a less..."

The word needed in this blank must be a pronoun that refers back to the "siblings" mentioned earlier in the passage. The phrase "one of" is typically followed by a plural pronoun in the object case when referring to a group of people or things.

Evaluating the Options for the Blank

Let's examine the given options for the blank "one of ______":

1. they
2. their
3. those
4. them

Option 1: they

'They' is a subject pronoun. Subject pronouns are used as the subject of a sentence or clause (e.g., They sing well). It is not used directly after the preposition 'of' in this context. So, "one of they" is grammatically incorrect.

Option 2: their

'Their' is a possessive adjective. It is used before a noun to show possession (e.g., their house, their singing). It cannot stand alone after 'one of'. So, "one of their" doesn't make sense in this structure.

Option 3: those

'Those' is a demonstrative pronoun or adjective. While "one of those" can be grammatically correct, it often refers to specific items or people previously pointed out or distinguished in some way ("one of those cakes", "one of those students I mentioned"). In the context of simply referring back to "siblings" as a general group already introduced, "those" feels less natural and direct than a personal pronoun.

Option 4: them

'Them' is an object pronoun. Object pronouns are used after prepositions like 'of', 'for', 'with', 'to', etc., or as the object of a verb (e.g., I saw them). The phrase "one of them" is a standard grammatical construction used to refer to a single item or person from a group already mentioned. Since "siblings" is the group being referred to, "them" is the correct pronoun to follow "one of".

Determining the Correct Answer

Based on the analysis of the grammar and the context of the passage, the phrase "one of" requires a plural object pronoun to refer to the siblings. The pronoun that fits this description and correctly completes the phrase is 'them'.

Using 'them', the part of the sentence becomes: "...one of them invariably has a less..." This correctly identifies one individual from the group of siblings.

Revision Table: Understanding Pronoun Types

Additional Information: The Phrase "One of"

The construction "one of the [plural noun]" or "one of [plural pronoun]" is very common in English. It is used to talk about one member or item from a larger group.

• When followed by a noun phrase, the noun is always plural (e.g., one of the books, one of the reasons).
• When followed by a pronoun referring back to a previously mentioned group, the pronoun is a plural object pronoun (e.g., one of us, one of you, one of them).
• Even though the phrase "one of..." refers to a single item, the verb that follows usually agrees with "one" and is therefore singular (e.g., One of them is missing; One of the books is old). However, in relative clauses following "one of...", the verb can sometimes be plural depending on the specific meaning intended, though the singular is generally safer and often preferred. The example sentence here uses "has", which is a singular verb, correctly agreeing with "one".

Understanding how to use pronouns correctly, especially after prepositions and in common phrases like "one of", is crucial for accurate and natural English.