"I worry because so many clever and decent people were killed," said high school student Pawel Kwas, 17.
“我担心，因为这么多聪明和正派的人遇难了，”17岁的高中学生帕维尔-克瓦说。
2
The aef of kwas negative in nk treatment while increased rapidly in npk treatment after10-year crop cultivation; k was also one of critical limited nutrients for crop yield .