——Do you have any idea when the project will be carried out?—No but I have heard that it

问题补充：

——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

答案：

(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。