Which of the following sentences is in active voice?

The sentence "Brenda bought a bike" is in active voice because the subject of the sentence (Brenda) performs the action of the verb (bought) directly on the object (a bike). In sentences written in active voice, the structure typically follows a clear pattern where the subject comes first, followed by the verb and then the object, making it straightforward and dynamic.

In contrast, the other sentences utilize passive voice construction where the action is performed on the subject rather than by the subject. For example, "A bike was bought by Brenda" and "The bike was being bought by Brenda" both feature the object (the bike) at the beginning, indicating that it is receiving the action rather than performing it. Similarly, "The bike is bought" focuses again on the object as the subject of the sentence, further illustrating passive voice. Understanding this distinction is crucial for mastering sentence structure and enhancing clarity in writing.