Given the following sentence and word, create a new sentence using the word.
Sentence: She had a dog.
Word: envelope
She sealed the letter and placed it in an envelope before walking her dog.
Complete the following task based on the instruction and optional input provided.### Instruction:
Given the following sentence and word, create a new sentence using the word.

### Input:
Sentence: She had a dog.
Word: envelope

### Output:
She sealed the letter and placed it in an envelope before walking her dog.