It’s so late. Why not write the report tomorrow —But I don’t know _________ I can do it if not now.

He had to pause from time to time to wipe the sweat from his forehead, because the airconditioningsystem ________. [ ]

The number of giant pandas is getting ______ because their living areas are becoming farmlands.

Timmy tells me that you find_____on theInternet.

have seen, the focus of medical care in our society has been __________ from curing diseases to preventing diseases—especially in terms of changing our many unhealthy behaviors.