题目

The computer was used in teaching. As a result, not only     , but students became more interested in the lessons.A. saved was teachers’ energy                               B. was teachers’ energy savedC. teachers’ energy was saved                                D. was saved teachers’ energy 答案：B解析：考查特殊句式：倒装句，根据语法知识：not only 是具有否定意义的连词，雇用半倒装，也就是B18．已知：25℃时，HCOOH的电离平衡常数K=1.75×10-5，H2CO3的电离平衡常数K1=4.4×10-7，K2=4.7×10-11．下列说法正确的是（　　）A．向Na2CO3溶液中加入甲酸无明显现象产生B．25℃时，向甲酸中加入NaOH溶液，HCOOH的电离程度和K均增大C．向碳酸中加入NaHCO3固体，c（H+）减小D．向0.1 mol•L-1甲酸中加入蒸馏水，c（H+）增大