Failure is never pleasurable, but it can make a positive contribution to your li

Failure is never pleasurable, but it can make a positive contribution to your life_____ you learn to use it.

A. since     B. once      C. until       D. unless

试题答案

B

解析:

主要测试连词。解此类试题的关键在于理解所给答案的意思，结合语境逐一排除。此句子中表示：一旦您学会了利用它，将对您的人生其积极作用。所以选择：once。