根据句意，用所给单词的适当形式填空。
How ____________you are to make such a mistake!  (careless)
I can’t understand his          (silent) on such an important matter.
If you take more exercise,  you will be               (health).
To everyone’s     , still many people are trapped under stones after the earthquake. (sad)
Li Ming goes to see his grandparents at a ________ (fix) date every month..