Generate a sentence using the words "grass," "caterpillar," and "rainbow."
Amid the dewy grass, a whimsical caterpillar admired the vibrant colors of the rainbow arching across the sky.
Complete the following task based on the instruction and optional input provided.### Instruction:
Generate a sentence using the words "grass," "caterpillar," and "rainbow."

### Output:
Amid the dewy grass, a whimsical caterpillar admired the vibrant colors of the rainbow arching across the sky.