Unluckily, the poor girl got a(n) ______ disease, which even doctors couldn't name.
Don’t ______ to contact me if you need any more information.
Come and see me whenever ______.
The thought ______ he might fail in the exam worried him a lot.
The noise was so ______ that he was so ______ that he stayed awake the whole night.
It suddenly ______ to me that we could use a computer to do the job.