Cut 1 pita bread in half. Prepare a salad of 1 1/2 cups of chopped romaine lettuce, 1/4 cups of chopped cucumber, 1/4 cup chopped tomatoes, 2 T. of chopped celery, 1 T. of diced green pepper, 1 ounce of crumbled feta cheese, and 2 medium black olives finely sliced. Toss with 2 T. of your favorite low calorie, low fat Greek salad dressing. Stuff each half of the pita bread with half of the salad.