This question tests your understanding of gerunds and perfect infinitives in English grammar. The goal is to complete the second sentence so that it has the same meaning as the first one.

The original sentence is: "It was a tragedy that she was killed on her wedding-day."

We need to transform this into: "To _____ was a tragedy."

Let's break down the original sentence:

• The subject is the entire clause: "that she was killed on her wedding-day".
• This clause describes an event that happened in the past.
• The verb "was killed" is in the passive voice because the subject (she) is receiving the action (was killed).

To transform this clause into a phrase that can follow "To", we need to use an infinitive form. Since the event is completed in the past, we must use the perfect infinitive, which is "to have + past participle".

Furthermore, because the original meaning is passive (she was killed), the infinitive must also be in the passive voice. The structure for a perfect infinitive in the passive voice is: "to have been + past participle".

Therefore, the correct phrase to fill in the blank is "have been killed on her wedding-day". The complete sentence becomes: "To have been killed on her wedding-day was a tragedy." This correctly and grammatically preserves the original meaning of a past, passive event.

Why the other options are incorrect:

• "being killed on her wedding-day": This uses a gerund ("being") instead of an infinitive ("to have been"). While a gerund could be the subject ("Being killed... was a tragedy"), the sentence structure specifically calls for an infinitive because it starts with "To".
• "killed on her wedding-day": This is just a past participle phrase, not a complete infinitive. It lacks the necessary "to have been" to show the past passive action.
• "have killed on her wedding day": This is in the active voice ("to have killed"). It changes the meaning to suggest that "she" did the killing, which is the opposite of the original sentence where she was the one killed.

Related Topics & Formulae

Infinitives: The base form of a verb, usually preceded by "to" (e.g., to be, to go, to see).

Perfect Infinitive: Used to refer to a time before that of the main verb.
Structure: $\mathrm{to}\mathrm{have}+\mathrm{past}\mathrm{participle}$
Example: "She claims to have seen a ghost." (The seeing happened before the claiming).

Passive Infinitive: Used when the subject of the clause receives the action.
Structure: $\mathrm{to}\mathrm{be}+\mathrm{past}\mathrm{participle}$
Example: "The car needs to be washed."

Perfect Passive Infinitive: Combines both concepts for a past, passive action.
Structure: $\mathrm{to}\mathrm{have}\mathrm{been}+\mathrm{past}\mathrm{participle}$
Example: "He was relieved to have been found."