Fred believed that his friend_______ by his employer a month or so ago.
A、had been promoted
B、has been promoted
C、has promoted
D、had promoted
【正确答案】：A
【题目解析】：A employer雇主，老板；or so大约；promote提升，升职。通过believed我们看出来，这句话的语境是过去时，提升这个动作发生在过去的过去，用过去完成时。答案就看Ａ，Ｄ两个选哪个呢？他的朋友是被提升，所以用被动语态，显然用Ａ被动语态。
