Yes. The sentence with correct parallel structure would be as follows. The doctor known only that her patient would improve, but also knew that her patient would [can't understand the sentence after that, but nevertheless it is still faulty].
The answer is yes. However, the other respondent provided you with an inaccurate (and non-parallel) sentence correction. The correct syntax -- and parallel structure -- is... The doctor not only knew that her patient would improve, but she also knew that he would completely recover.
It means there was a soldier at each window with a gun ready to shoot down the highwayman, which is death, and there were 2 at her window which was worse than 1 which was hell.
