2. 外语
  3. __________(在1世纪末就开始投入使用), this kind of energy had brought great convenience for human beings.

__________(在1世纪末就开始投入使用), this kind of energy had brought great convenience for human beings.

admin2010-10-14  85
问题 __________(在1世纪末就开始投入使用), this kind of energy had brought great convenience for human beings.
选项
答案Having come into use at the end of 18th century
解析 考查分词作状语从句的表达。看整句时态，完全是描述过去的事情，所以要用分词的完成式having done的形式。“投人使用”译为come into use。
转载请注明原文地址:https://kaotiyun.com/show/Np87777K
0

大学英语四级

相关试题推荐
随机试题
最新回复(0)