Greek Chicken Pita

6½-inch whole wheat pita (cut in half to make pockets)

cooked chicken breast, boneless, skinless (cut into 1-inch cubes)

medium tomato (chopped)

chopped cucumber

chopped red onion (optional)

dried oregano

fresh lemon juice

shredded romaine lettuce

crumbled feta cheese (about 1/2 oz.)