Question

Fill in the blank with a suitable modal:
John is expecting you to phone him. You ______ call him as soon as you get free.

• A. must
• B. can
• C. should
• D. will

Answer 1

The correct option is C should

Modal Verbs show us the attitude of the speaker to what is being said or done. The term "modal" means expressing mood and mood is a way to express the attitude of the speaker.

The given sentence is firstly set in present tense and secondly according to the meaning of the sentence it expects an advice.

Option C is the correct answer because it expresses an advice regarding what is correct.

Whereas option A expresses something with strong assurance which is supposed to happen.

option B expresses ability

Option D expresses certainty in performing an action in future.