void Update () {

    　　if(Input .GetKeyDown (KeyCode .W ))

        {

            StartCoroutine ("Test");

        }

    }

    IEnumerator Test()

    {

        while (Cube1 .position .x<)

        {

            Cube1 .Translate (transform .right **Time .deltaTime );

            yield return null;

        }

        yield return new  WaitForSeconds();

        while (Cube2 .position .x<)

        {

            Cube2 .Translate (transform .right **Time .deltaTime );

            yield return null;

        }

    }