- Whats wrong with you Madam? - Ive lost my valuable painting. But a week had gone by

问题补充：

- Whats wrong with you, Madam?

- Ive lost my valuable painting. But a week had gone by I knew it was missing.

A. while

B. since

C. until

D. before

答案：

A. while

B. since

C. until

(答案→)D. before

解析：句意：——太太，你怎么啦？——我丢了我的贵重的油画。但是一周过去了，我才知道它丢了。A. while当……时候； B. since 自从； C. until 直到； D. before在……之前；。根据knew，和had gone可知，在知道之前，那幅画已经丢了，故用连词before。故选D。