Question

Choose the correct passive form from the options given.
How old are these houses? When ________ built?
A. Are they
B. Were they
C. Are them
D. Were them

Answer 1

Hint: The verb’s voice defines in grammar the relationship between the action represented by the verb and the participants described by its arguments. There are two types of voices: active and passive.

Complete answer:
Voice, mood, tense, person, and number are the five properties of verbs in English grammar; we are bothered with voice here. The verb is in the active voice when the subject is the agent or doer of the action. The verb is said to be in the passive voice when the subject is the patient, target or under-goer of the action. Sentences have a solid, direct, and consistent tone in the active voice. Transitive verbs have both active and passive forms. When the subject is acted on by the verb, a sentence is in the passive voice. The passive voice is often built with an associated form of to be along with the past participle of the verb. Doing this often typically introduces a preposition. That sounds much more complex than it is-it is actually very easy to detect a passive voice.

The given sentence is in passive voice. 'Old' clarifies that the statement is in the simple past tense. We need "was / were", a noun / pronoun and the verb in the past participle form to form a question in the simple past tense. ‘Were they’ could be used in a passive voice here. As the subject 'houses' is plural, 'were' can be used and 'they' can be used as a pronoun for the houses.

Hence the correct answer is option ‘B’

Note: If you find difficulty in changing voice, always look at the voice change rules in a grammar book. This will be of great help to easily find out the answer.