At that moment came a _____ noise, leaving people _____.
American Indians ______ about five percent of the U.S. population.
The problem of global warming is serious. ______, the sea levels have risen a little.
At the beginning of class, the noise of desks ______ could be heard outside the classroom.
Yesterday morning he got up earlier than ______, for it was not a(n) ______ day.
The medical reform in that country turns out to be ______ failure, but as we know, success often comes after ______ failure.