2道高中英语单选求解析

2道高中英语单选求解析1.—Was the flight late again,Tim?—luckily,no.I hadn‘t waited long()my wife arriveA.until B.before(为啥不选until)2.Only when the computer came into being ___was there____ any possibility that man could start his journey far into outer space.（为什么不能用was it）