A passive construction occurs when you make the object of an action into the subject of a sentence. That is, whoever or whatever is performing the action is not the grammatical subject of the sentence. Take a look at this passive rephrasing of a familiar joke:
Why was the road crossed by the chicken?
Who is doing the action in this sentence? The chicken is the one doing the action in this sentence, but the chicken is not in the spot where you would expect the grammatical subject to be. Instead, the road is the grammatical subject. The more familiar phrasing (why did the chicken cross the road?) puts the actor in the subject position, the position of doing something—the chicken (the actor/doer) crosses the road (the object). We use active verbs to represent that "doing," whether it be crossing roads, proposing ideas, making arguments, or invading houses (more on that shortly).
Once you know what to look for, passive constructions are easy to spot. Look for a form of "to be" (is, are, am , was, were, has been, have been, had been, will be, will have been, being) followed by a past participle. (The past participle is a form of the verb that typically, but not always, ends in "-ed." Some exceptions to the "-ed" rule are words like "paid" (not "payed") and "driven." (not "drived"). Here's a sure-fire formula for identifying the passive voice:
form of "to be" + past participle = passive voice
For example:
The metropolis has been scorched by the dragon's fiery breath.
When her house was invaded, Penelope had to think of ways to delay her remarriage.
NOTE: forms of the word "have" can do several different things in English. For example, in the sentence "John has to study all afternoon," "had" is not part of a past-tense verb. It's a modal verb, like "must," "can," or "may"—these verbs tell how necessary it is to do something (compare "I have to study" versus "I may study"). And forms of "be" are not always passive, either—"be" can be the main verb of a sentence that describes a state of being, rather than an action. For example, the sentence "John is a good student" is not passive; "is" is simply describing John's state of being. The moral of the story: don't assume that any time you see a form of "have" and a form of "to be" together, you are looking at a passive sentence. "I have to be on time for the concert," for example, is not passive. Ask yourself whether there is an action going on in the sentence and, if so, whether whoever or whatever is doing that action is the subject of the sentence. In a passive sentence, the object of the action (e.g., the road) will be in the subject position at the front of the sentence. There will be a form of be and a past participle. If the subject appears at all, it will usually be at the end of the sentence, often in a phrase that starts with "by" (e.g., "by the chicken").
Rosa León
AO5F
