Choose the sentence in which the modal has been used incorrectly:

The correct answer is Option (2) → You ought return the extra change to the shopkeeper.

Ought is followed by to:

• The given sentence says “ought return”.
• Ought shows a moral duty, and it is always followed by to + base verb (the simple form of the verb, like go, eat).
• Here “to” is missing, so the sentence is wrong.
• Corrected: You ought to return the extra change to the shopkeeper.

Why the Other Options are Incorrect?

Option 1: You need not wait for me after the tuition class. This sentence is correct. “Need not” is a modal here. It shows that waiting is not necessary and takes the base verb “wait”.

Option 3: Little Mohan dared to climb the old banyan tree alone. This sentence is correct. Here “dared” is an ordinary verb in the past, so it can take “to climb”.

Option 4: May you win the gold medal at the state athletics meet. This sentence is correct. “May” at the start of a sentence can express a wish for someone.