Question

He realized his mistakes and took action to reduce the loss _______ it was too late.

A．until

B．when

C．before

D．as

Answer 1

C

解析试题分析：句意:他意识到了他的错误，在还来得及之前采取措施减少损失。until直到…时候；when 当…时候；before 在…之前；as 当…时候。这里应该是表示在太晚之前，也就是还来得及。故选C。
考点：考查连词。