An author can reveal character development to the reader through

a variety of techniques including:

1. Dialogue: Through conversations between characters, the author can reveal their thoughts, feelings, and motivations. Dialogue can also show how characters interact with one another and how their relationships evolve over time.

2. Actions: The choices characters make and how they respond to different situations can reveal their character development. For example, a character who starts out as timid and afraid may gradually become more confident and courageous as the story progresses.

3. Thoughts and feelings: The author can give insight into a character's inner thoughts and emotions through narration or internal monologues. This can help the reader understand the character's motivations and how they are changing throughout the story.

4. Flashbacks or memories: By including flashbacks or memories from a character's past, the author can provide context for their behavior and show how their experiences have shaped who they are. This can help the reader understand their character development more deeply.

5. Interactions with other characters: How a character interacts with others can reveal a lot about their personality, values, and growth. Paying attention to how characters communicate and relate to one another can provide valuable clues about their development.

Overall, character development is a key aspect of storytelling, and authors use a combination of these techniques to reveal how their characters change and grow over the course of a narrative. By paying attention to these details, readers can gain a deeper understanding of the characters and their journey.