You should have been more patient that customer；I’m sure that selling him the watch was a possibility.
A. of
B. with
C. for
D. at
网友回答
A. of
(答案→)B. with
C. for
D. at
解析：句意：你应该对客人耐心点，我确信卖给他手表是有可能的。be patient of能容忍的；这里be patient with对某人有耐心，这是固定短语，根据句意故选B。