Question

the librarian said to the student you _not speak loudly option I can 2 would 3 must 4 might

Answer 1

The correct option is option 3 must.

Explanation:

‘Must’ is a modal verb that is used to express something necessary and very important. For example to tell people a rule or law, we use this modal. An example of the usage of modal ‘must’ is: Vehicles must not be parked in front of the entrance. 

Answer 2

Correct verb:

The librarian said to the student you 3. must not speak loudly

Explanation:

• In the given sentence, the word "must" is used as verb.
• The word is expressing necessity which means should or be obliged to.
• This word is used to define the future tense and used to emphasis. It is also used to show something certain to be true.
• The past tense of "must" is "might."