One in five humans ___ access to safe drinking water by 2080．
A．is said lacking B．is said to lack
C．are said to lack D．are said lacking
It is hard to imagine what I ___ today if I hadn't been admitted to Nankai Middle School 15 years ago.
A．would have done B．will do
C．am doing D．would be doing
Not until they left school ___ how much their teachers loved them and helped them．
A．they realized B．did they realize
C．they had realized D．had they realized
___ three times in a row, the boxer decided to make a fourth attempt, though．
A．Having defeated B．To have defeated
C．Having been defeated D．To defeat
___ is well known is that Africa had contacts with India and the Red Sea civilizations from the earliest times．
A．As B．It C．What D．That
The truly homeless are the rich who __ _ their home into a hotel hall．
A．will turn B．turned
C．are turning D．have turned
