Question

Unlike the brown sparrow, the passenger pigeon (was slaughtered indiscriminately, had been slaughtered indiscriminately) and became extinct in 1914.

Short answer

The correct answer is 'had been slaughtered'. The sentence should read: 'Unlike the brown sparrow, the passenger pigeon had been slaughtered indiscriminately and became extinct in 1914.'

Step-by-step solution

Understand the Sentences Context

First look at the sentence and try to understand its context. The sentence is referring to the slaughtering of the passenger pigeon and its extinction in 1914.

Determine the Correct Verb Tense

Next, think about which verb tense is more appropriate. The action of slaughtering occurred before another action or state of being (extinction), which suggests that the past perfect tense is more suitable here.

Replace the Words in Brackets with the Correct Verb Tense

Finally, substitute the verb phrase in brackets with 'had been slaughtered'. This indicates that the event of slaughtering finished before the following event of passenger pigeons becoming extinct.