he could call the police, the thieves had run away with the suitcase, leaving him shocked and helpless.
A. Before
B. Until
C. Because
D. Unless
网友回答
(答案→)A. Before
B. Until
C. Because
D. Unless
解析：A 考察连词。句义：他还没有来得及报警，小偷已经带着手提箱逃跑了。这使他感到震惊和无助。Before在…之前发生。A正确。