Choosing the Right Verb for "The Sudden Noise" Sentence

The question asks us to find the most suitable word to complete the sentence: "The sudden noise _______ the horse." This requires us to choose the correct form of the verb based on the subject and the context.

Let's look at the subject of the sentence: "The sudden noise". This subject is singular. We need a verb form that agrees with a singular subject and makes sense in the context of the sentence, which describes what the noise did to the horse.

Analyzing the Verb Options

Let's examine each option provided:

• has frighten: This option uses "has", which is appropriate for a singular subject in the present perfect tense. However, "has" must be followed by the past participle form of the verb, which is "frightened", not the base form "frighten". So, "has frighten" is grammatically incorrect.
• have frightened: This option uses "have". "Have" is used with plural subjects (like "noises") or pronouns like "I", "you", "we", and "they". Since the subject "The sudden noise" is singular, "have" is not the correct helping verb to use here. Also, the phrase uses the past participle "frightened", which is the correct form after a helping verb like "have" or "has", but the helping verb itself is wrong for the singular subject.
• have frighten: This option uses "have", which is incorrect for a singular subject ("The sudden noise"). Additionally, it uses the base form "frighten" after "have", instead of the past participle "frightened". This makes the verb phrase grammatically incorrect on two counts.
• frightened: This is the simple past tense form of the verb "to frighten". The simple past tense describes an action that happened and was completed in the past. The verb "frightened" agrees with the singular subject "The sudden noise" and fits the context of a single event (the noise occurring) causing the horse to be scared. This form works directly with the singular subject without needing a helping verb like "has" or "have" to form a simple past tense sentence.

Selecting the Most Appropriate Option

Based on the analysis, the option "frightened" is the only grammatically correct verb form that fits the sentence "The sudden noise _______ the horse." It uses the simple past tense, which correctly shows that the action happened in the past and is complete. It also works correctly with the singular subject "The sudden noise".

The completed sentence is: "The sudden noise frightened the horse."