Vaccine Effectiveness Grammar Improvement

This question focuses on improving a specific phrase within a sentence about vaccines and disease prevention.

The original sentence provided is:

Deactivated viruses form the basis of many vaccines known for their effectiveness to prevent diseases.

The goal is to find the most grammatically correct and natural-sounding prepositional phrase to follow the noun effectiveness.

Effectiveness Phrase Analysis

When discussing the capability or success in performing an action, the noun effectiveness is typically followed by the preposition in and a gerund (the -ing form of a verb). This construction indicates the specific area or manner in which the effectiveness is demonstrated.

Let's evaluate each option provided:

• 1. to prevent: Using effectiveness to prevent is not the standard idiomatic construction in English. While adjectives like 'effective' can sometimes be followed by 'to + infinitive', the noun form 'effectiveness' pairs more naturally with 'in + gerund'.
• 2. in preventing: This option uses the correct preposition in before the gerund preventing. This aligns with common English usage, such as "The medicine is effective in treating the condition" or "Her effectiveness in managing projects is notable". Therefore, "effectiveness in preventing diseases" is the most appropriate phrasing.
• 3. with preventing: The preposition with generally implies accompaniment or the tool used. It does not correctly indicate the domain or area of effectiveness. This option is grammatically incorrect in this context.
• 4. preventing: Omitting the necessary preposition before the gerund preventing results in an incomplete and grammatically incorrect phrase.

Correct Phrase Selection

Comparing the options, in preventing is the best choice because it follows the standard grammatical rules for using the noun effectiveness.

The corrected sentence reads:

Deactivated viruses form the basis of many vaccines known for their effectiveness in preventing diseases.