Complete the sentence with suitable alternatives from the options given below.
Sumit is obedient, someone else ________ done it.
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → must have
Complete sentence: Sumit is obedient, someone else must have done it. The fact: Sumit is obedient, so he would not have done the wrong thing. The conclusion: someone else must have done it.
| Option | Meaning and use | Example |
|---|---|---|
| (1) must have (answer) | Must have done expresses a firm conclusion about something in the past, drawn from the facts we know. | The ground is wet; it must have rained at night. |
| (2) should have | Should have done shows what was the right thing to do but was not done. It gives advice or blame, not a conclusion. | You should have told me earlier. |
| (3) might | "Might done" is not grammatical. A past possibility needs might have + past participle. | – |
| (4) can have | Can have is not used in positive statements about the past. English uses "could have" or "may have" for a past possibility. | – |