Choose the most appropriate option to complete the given sentence:-
Ashwini insisted that the committee must _____ the matter thoroughly before making any decision.
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → investigate
Complete sentence: Ashwini insisted that the committee must investigate the matter thoroughly before making any decision. "Must" comes before the blank, so the base form "investigate" is needed.
| Option | Meaning and use | Example |
|---|---|---|
| (1) investigates | The -s form is the simple present for a singular subject. It can never follow a modal ("must investigates" is wrong). | The detective investigates every clue himself. |
| (2) investigating | The -ing form needs a helping verb such as "be" (must be investigating). "Must investigating" is wrong. | The police are investigating the theft. |
| (3) investigated | The past form cannot follow "must". For a past sense we would say "must have investigated". | The officer investigated the case last year. |
| (4) investigate (answer) | A modal verb such as must is always followed by the base form of the verb (must go, must check). Even without "must", "insisted that" takes the base form (insisted that the committee investigate). | The doctor said that I must rest for a week. |
Contrast: "must" is followed by the base form (must investigate). "Must be investigating" and "must have investigated" need a helping verb.