Make marinade by combining lemon juice,Worcestershire sauce,oil,soy sauce,mustard,garlic.Cut beef into 1" chunks,then put in marinade.Cover and marinate in refrigerator for 12 hours or more... Cut vegetables into chunks,making at least 8 pieces of each.Remove beef cubes from marinade,reserving marinade... On 4 medium or long skewers,alternate pieces of meat and vegetables.Grill over hot coals,basting occasionaly with marinade,for about 15 minutes,turning shewers regularly.(Allow 5 to 10 minutes longer for well done meat.).Serve hot.Makes 4 servings....