Refreshing Summer Salad with Tomatoes, Cucumbers and Onions

2 medium cucumbers, sliced2 medium tomatoes, sliced or diced1 medium onion, thinly sliced1/4 cup white vinegar or apple cider vinegar1/4 cup olive oil1 teaspoon sugar (optional)1 teaspoon dried oregano or Italian seasoningSalt and pepper to tasteFresh parsley or basil for garnish (optional)Prepare the Vegetables: Wash and slice the cucumbers, tomatoes, and onion. Place them in a large bowl or directly into a jar for easy storage.Make the Dressing: In a separate small bowl, whisk together the vinegar, olive oil, sugar (if using), oregano, salt, and pepper.Combine: Pour the dressing over the vegetables. Toss gently to coat everything evenly.Marinate: Cover and refrigerate for at least 1 hour to allow the flavors to meld together. For best results, let it sit overnight.Serve: Serve chilled as a refreshing side dish or light snack. Garnish with fresh parsley or basil if desired.Enjoy this simple and flavorful salad!