It's dinner time!

Ingredients

• 1 onion, chopped
• 5 carrots, chopped
• 5 stalks celery, chopped
• 5 cloves garlic, chopped
• 4 cups water, or as needed
• 1 teaspoon olive oil, or to taste
• 2 bay leaves
• salt and ground black pepper to taste
• 1 (16 ounce) package dry lentils
• 1 teaspoon vinegar, or to taste