Choose the most suitable option to replace the underlined part of the sentence. If the sentence is already correct, select 'No substitution required".
The old lady was unable to climb stairs because her legs is aching constantly since morning.
Show answer & explanation
Correct answer: B
Explanation
Subject-Verb Agreement: The subject "legs" is plural, so the verb must also be plural. "Is" and "has" are singular, while "have" is the correct plural form.
Tense Consistency: The phrase "since morning" indicates an action that started in the past and continued up to a certain point. This requires a perfect continuous tense.
Grammatical Structure: The present perfect continuous structure is used here to describe a condition that has been ongoing throughout the day.
The correct option is “have been aching constantly”.