Green Salad with Avocado

1 tsp. sugar
2 Tbsp. lemon juice
1/4 c. olive oil
Salt and pepper to taste
1/2 cucumber, sliced
1 head iceberg lettuce
1 green bell pepper, cored, deseeded, sliced
1/2 oz. watercress
1 avocado

Tear lettuce into pieces and place in salad bowl. Divide watercress into sprigs and add to bowl with cucumber and green pepper. Peel avocado, halve and remove stone. Cut avocado into slices just before serving, add to salad and toss well. Whisk together the lemon juice, oil, sugar, salt and pepper. Pour over salad, toss well. Serves eight.