The following sentence has been divided into four segments. Identify the segment that contains a grammatical error. My sister, Juliet, / got married / as her / was 23.

Correct — A. The last segment is was 23 — a finite verb with nothing in front of it to do the being. That empty slot takes a subject pronoun, so the segment must read 'as she was 23'.

Her is the object form (and the possessive determiner). It works after a verb or a preposition — 'told her', 'with her' — but never as the subject of a clause.

So the faulty segment is 'as her', option (a).

Why the others are wrong

• (b)
  My sister, Juliet, — My sister, Juliet, is an appositive correctly fenced by a comma on each side. The name renames the subject and the punctuation is complete.
• (c)
  got married — got married is the normal past form of 'get married'. It needs no object and no preposition here, so the segment stands.
• (d)
  was 23. — was 23 is right once a subject is supplied. English states age with 'be' plus the number, and the past tense matches 'got married'.

English pronouns still carry case. The subject forms are I, he, she, we, they, who. The object forms are me, him, her, us, them, whom.

A finite clause — any clause with a tensed verb — needs an overt subject in the subject form. 'as she was 23' is grammatical, 'as her was 23' is not.

Her is the trap because it does double duty: object pronoun in 'I saw her' and possessive determiner in 'her book'. That range makes it feel usable in every slot, including the one slot it cannot fill.

Key facts

• Subject pronouns: I, you, he, she, it, we, they.
• Object pronouns: me, you, him, her, it, us, them.
• A tensed clause in English must have a subject in the subject form.
• Her is both an object pronoun and a possessive determiner.

Common traps

• Accepting 'as her' because it sounds like everyday speech.
• Marking the appositive commas around Juliet as the error.

No directly related past PYQ was found.