单项选择题
Just as people differ in their ability to hear sound, （） differ in their appreciation of sounds.
A．so also do they B．so they also do C．also so do they D．so do they also
单项选择题 Seldom（）any mistake during his past ten years of service there.
单项选择题 There are forty students in our class.（）of them are League members.
单项选择题 By the end of this year, they（）the construction of the subway.
