题目

Never before _______in greater need of modern public transport than it is today. A. has this city been                 B. this city has been      C. was this city                      D.  this city was. 答案：A下列各种关于溶液酸碱度的阐述中，不正确的是　　　[　　] A.溶液的酸碱度就是所指溶液酸碱性强弱的程度 B.pH就是表示溶液酸碱度的数值 C.溶液的pH由0开始逐渐增大，说明溶液的酸性逐渐增强，碱性逐渐减弱 D.测定溶液pH的精确方法用pH计，简易方法用pH试纸