–What’s the matter, doctor? --Nothing serious. Take the medicine according to the ______.

 It came as a great _______ to the parents that their son finally came back safe and sound.  

After the earthquake, the government turned a school into a      for the victims of the earthquake.

The cat ____ Mimi belongs to _____.

I listened to Dr. Johnson’s lecture about biology, but I failed to get its key ____.