In the following sentence, the blank must be filled with a suitable word. My grandmother exercise regime is to walk the mall at a __________ pace.

Introduction / Context:

This blank filling question tests your understanding of collocations, that is, natural word combinations in English. The sentence describes a walking exercise routine in a shopping mall and asks you to choose the adjective that best describes the pace or speed of walking in a healthy and idiomatic way.

Given Data / Assumptions:

• Sentence: My grandmother exercise regime is to walk the mall at a __________ pace.
• Options: potent, brisk, strong, vital.
• The context is physical exercise that is beneficial but suitable for an older person.
• We assume that the pace is neither extremely slow nor dangerously fast.

Concept / Approach:

In health and fitness contexts, the phrase brisk walk or brisk pace is very common. It means fairly quick and energetic but still comfortable, especially for cardiovascular exercise. The other adjectives potent, strong, and vital may appear in other collocations but do not naturally describe pace in the same way. Recognising such set expressions is crucial for scoring well in vocabulary sections.

Step-by-Step Solution:

Verification / Alternative check:

Imagine reading a health article. You are likely to see sentences like Doctors recommend a brisk walk for thirty minutes a day. You would not normally read about a potent pace, strong pace, or vital pace in standard English. This real world usage check confirms that brisk is the most natural and idiomatic choice in the blank.

Why Other Options Are Wrong:

Potent is wrong because it refers to power or effectiveness in contexts like medicine or influence, not walking speed.

Strong is wrong because it collocates with words like personality, flavour, or wind, and not commonly with pace in this sense.

Vital is wrong because it describes importance or necessity, not the tempo of physical movement.

Common Pitfalls:

A common mistake is to choose any positive sounding adjective without considering collocation. Examiners design such questions to see whether you know the exact phrase used by native speakers. Another pitfall is to overthink and doubt the familiar combination brisk pace because it seems too obvious. When a simple and widely used phrase fits, it is often the correct answer.

Final Answer:

The correct word is brisk, giving the phrase at a brisk pace.