问题补充:
-----What is the noise?
-----Oh, I forgot to tell you. The new machine .
A. was tested
B. will be tested
C. is being tested
D. has been tested
答案:
A. was tested
B. will be tested
(答案→)C. is being tested
D. has been tested
解析: 根据-What is the noise,可知是现在正在进行的动作,所以新机器应是正在被测试。用现在进行时态的被动语态。