I don't believe we've met before I must say you do look familiar.A. thereforeB. althoughC

问题补充：

I don believe weve met before, I must say you do look familiar.

A. therefore

B. although

C. since

D. unless

答案：

A. therefore

(答案→)B. although

C. since

D. unless

解析：句意：尽管我一定说你确实看起来熟悉，但我相信我们以前没见过面。根据句意只有although符合题意。

【考点定位】考查状语从句的连接词。