Delicious Light Waldorf Salad

SALAD: 1 cup diced celery 1 cup diced crisp apples 1/2 cup chopped walnuts 1/2 cup seedless red grapes   DRESSING: 1/2 cup unsweetened greek lowfat yogurt mixed with 1 tbs lemon juice   INSTRUCTIONS: Place all salad ingredients in a large serving bowl.  Toss with dressing and keep refrigerated until ready to serve.   NUTRITIONAL INFO: 179 cal / 22g protein / 10g fat / 13 carbs makes 1 serving