Take a bowl and place couscous in it.
Pour 400ml water in the kettle to heat. When the water boils, pour it over couscous. Let it stand for 5 minutes but keep it covered. Then, uncover it and put it to cool at room temperature.
Then take a medium sized bowl and combine oil, lemon juice, salt and pepper in it. Blend them with other ingredients; parsley, cucumber, basil, spring onion and couscous and combine them until all the ingredients mix well.
Before serving, place it for at least 1 hour to make colder.
After that take a plate and line it with lettuce leaves and couscous mixture. Spoon over the leaves and dress them with lemon wedges. The Couscous Cucumber Salad is ready to serve.