I wasn't sure if he was really interested or if he ________ polite.
A．was just being
B．will just be
C．had just been
D．would just be
I wasn't sure if he was really interested or if he ________ polite.
A．was just being
B．will just be
C．had just been
D．would just be
A
解析：根据句意判断应用过去进行时，表示“(刚才)他是不是在表示礼貌”。句意：我不确定他是否真的感兴趣，或者是不是他只是在表示礼貌。