______ our horizons of thinking, but it also saves us time and energy.
Some experts think the wolfs team spirit for survival is ______ is needed in today's competitive culture.
Many experts believe that teachers' development is ______ the key to better education lies.
Great honors will be given to ______ have successfully rescued the victims of the earthquake.
The biggest surprise for John was ______ he was chosen as team captain.
The conference aims to develop business and let people think about ______ they can have a positive influence on the Earth.