out of the blue

Out of the blue, he received an email from an old friend he hadn't heard from in years.突如其来地，他收到了一封来自多年未联系的老朋友的电子邮件。

She called out of the blue and offered me the exact role I had been hoping for.她出乎意料地打电话给我，提供了我一直期望的那个职位。