——Do you have any idea when the project will be carried out?
—No, but I have heard that it was not until last month it was approved.
A. that
B. when
C. since
D. before
网友回答
(答案→)A. that
B. when
C. since
D. before
解析：句意：—你知道那个项目什么时候将被执行?—不知道,但我听说过,直到上个月才批准。强调句的结构：it was +强调的内容+that+剩余内容。not until last month是被强调的内容。故选A。