题目内容
By the middle of the 1920s the farthest corners of the earth explored.
A．are B．were C．have been D．had been
D
练习册系列答案
阅读快车系列答案
相关题目
阅读快车系列答案题目内容
By the middle of the 1920s the farthest corners of the earth explored.
A．are B．were C．have been D．had been
D
阅读快车系列答案