As many as 100 species of fish, some ____ to these waters, may have been affected by the pollution． 

How cold it is! We’ve never had ______ this winter．

 In today’s fast changing and competitive world, to be able to learn faster and more effectively is not merely desirable; it is ________.

It is ________ Beth to drink so much; I wonder if she is all right.

. Before radio and TV, music could only be heard _______, that is, you had to go to places where musicians gave performances.