The more one is _______ the English-speaking environment, the better he or she will learn the language.
Wind power is an ancient source of energy ________ we may return in the near future.
She showed the visitors around the museum,the construction ________ had taken more than three years.(2011·江西)
Julie was good at German,French and Russian,all of ________ she spoke fluently.(2011·湖南)
Care of the soul is a gradual process ________ even the small details of life should be considered.(2012·湖南)
The man showed us such a heavy stone ________ no one could lift it.