About the sixth century A. D. when few Europeans could read, the Chinese ____paper. (2 分) A. invented B. had invented C. have invented D. had been invented.

来源:学生作业帮助网 编辑:作业帮 时间:2024/11/06 05:12:35

About the sixth century A. D. when few Europeans could read, the Chinese ____paper. (2 分) A. invented B. had invented C. have invented D. had been invented.
About the sixth century A. D. when few Europeans could read, the Chinese ____paper. (2 分)
A. invented
B. had invented
C. have invented
D. had been invented.

About the sixth century A. D. when few Europeans could read, the Chinese ____paper. (2 分) A. invented B. had invented C. have invented D. had been invented.
B这是一个过去完成时,发生在 前半句话( 它已发生在过去时了)的前面