给出以下句子，使用Python将其中每个单词的首字母大写。
the quick brown fox jumps over the lazy dog.
```python
s = "the quick brown fox jumps over the lazy dog."
result = ' '.join(word.capitalize() for word in s.split())
print(result)
```

Output:
```
The Quick Brown Fox Jumps Over The Lazy Dog.
```