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

解析試題分析：句意:他意識到了他的錯誤，在還來得及之前采取措施減少損失。until直到…時候；when 當…時候；before 在…之前；as 當…時候。這里應該是表示在太晚之前，也就是還來得及。故選C。
考點：考查連詞。