The doctor finally gave up the ____ of medicine for full - time writing.
The river forms the __________ between the heavy industrial and light industrial areas of the city.
Measures have been taken __________ the spread of the HIV.
In __________ preparation for Shenzhou If, scientists need __________ knowledge of weather changes.
—Thanks so much for everything. You have certainly made my stay very pleasant. —__________.
—__________ for the fire! —It's OK. I'll be careful enough.