Explanations:The question requires the use of the present continuous tense to describe an action that is planned for the near future. The sentence "My sister _____ a piano lesson this evening" needs a verb form that indicates an action that will take place in the near future, specifically "this evening."
The present continuous tense is formed using the auxiliary verb "is," "am," or "are" followed by the present participle of the main verb. In this case, the subject is "My sister," which requires the auxiliary verb "is." The present participle of the verb "have" is "having." Therefore, the correct form is "is having."
Let's break down the structure of the present continuous tense:
1. **Auxiliary Verb**: The auxiliary verb used in the present continuous tense is "is," "am," or "are," depending on the subject. For the third person singular (he, she, it), the auxiliary verb is "is." For the first person singular (I), the auxiliary verb is "am." For all other subjects (you, we, they), the auxiliary verb is "are."
2. **Present Participle**: The present participle is formed by adding "-ing" to the base form of the verb. For regular verbs, this is straightforward (e.g., "play" becomes "playing"). For irregular verbs, the form may vary (e.g., "go" becomes "going").
3. **Time Reference**: The present continuous tense is often used with time expressions that indicate the near future, such as "tonight," "this evening," "tomorrow," "next week," etc. In this sentence, "this evening" is a clear indicator that the action is planned for the near future.
Other options are incorrect for the following reasons:
- **Option B (Having)**: "Having" is a non-finite verb form and cannot stand alone as the main verb in a sentence without an auxiliary verb. It would be used in a gerund or as part of a perfect tense.
- **Option C (Has)**: "Has" is a finite verb form used in the present perfect tense, which is not appropriate for describing an action planned for the near future. The present perfect tense is used to describe actions that have been completed at some point before now.
- **Option D (Have)**: "Have" is a finite verb form used in the simple present tense or as part of the present perfect tense, but it does not fit the context of an action planned for the near future. The simple present tense is used to describe habitual actions or general truths, not specific future plans.
Understanding the correct use of the present continuous tense is crucial for accurately describing actions that are planned for the near future. This tense is commonly used in everyday language to talk about events that are scheduled or expected to happen soon.