Question

Change the following sentence to passive form.

Dust and smoke cause smog.

• A. The smog is been caused by dust and smoke.
• B. Dust and smoke is caused by the smog.
• C. Smog was caused by dust and smoke.
• D. Smog is caused by dust and smoke

Answer 1

The correct option is D Smog is caused by dust and smoke

The ground rules to change active voice in passive voice are:

• The places of subject and object are interchanged.
• 3rd form of the verb (past participle) is always used as the main verb in the passive voice. This applies to all tenses.
• The word 'by' is generally used before the subject.

The given sentence is an example of simple present tense. The formula for simple present tense to convert a sentence in passive voice is Subject +To Be + past participle + by object.

Thus, the passive voice for the given sentence - Smog is caused by dust and smoke.

Hence, option D is the correct answer according to the rules.