16. She is as intelligent as her sister if not more.
17. You will not succeed unless you are optimistic.
19. Despite being ill, he attended the classes.
20. That man is aggressive by nature is a hard fact of life and no one can deny it.
That man is aggressive by nature is a hard fact of life which none can deny.
That man is aggressive by nature is a hard fact of life and no one can deny it ..
That man is aggressive by nature is a hard fact of life and not one can deny.
That man is aggressive by nature is hard for anyone to deny.