标题: 指代问题求教 [打印本页] 作者: wangwanwang 时间: 2014-10-16 19:52 标题: 指代问题求教 Whereas the use of synthetic fertilizers has greatly expanded agricultural productivity in many parts of the world, [an increase in their use can create serious environmental problems such as water pollution, and their substitution for more traditional fertilizers] may accelerate soil structure deterioration and soil erosion.
B. an increase in their use can create serious environmental problems like water pollution, and if substituted for more traditional fertilizers, it
C. if these fertilizers are used increasingly, they can create serious environmental problems such as water pollution, and if used as substitutions for more traditional fertilizers, they
D. the increased usage of these fertilizers can create serious environmental problems such as water pollution, while if substituted for more traditional fertilizers, this substituion
E. the increased usage of these fertilizers can create serious environmental problems like water pollution, while their subsitution for more traditional fertilizers