as though/if 虚拟语气的时态

The computer "teacher" was talking with its students asthough it _____ a human teacher.

请问各位老师，这个空填had been还是were。我看网上有答案说是were，我觉得had been对。谢谢各位！

As though/if引导的虚拟语气从句时态分两种状况：1）通常情况 2）特殊状况

通常情况是与目前事实/过去事实或以后事实相反的状况。与目前事实相反或怀疑目前的状况，从句用did/were表达；与过去事实相反，从句用had done/been表达；与以后事实相反或可能性不大时，从句用would/could/might+do.

特殊状况是从句的动作或状况与主句的动作或状况同时发生，从句则用过去时，包含从句正在发生的进行动作。

例：He looked as if he were sick. In fact, he was very strong.

She waved her hand as if she saw a taxi.

He acted as if he were smoking .

结论：as if /as though从句中动词时态须依据它发生在主句动词时态之前、之后、还是同时来确定。所以你的问题答案应该用were比较符合与主句是同时的一种状况。