Johnwaitedatthebus-stopfornearlyhalfanhour
问题详情：
John waited at the bus-stop for nearly half an hour _____ the bus finally arrived .
A. when B. as C. before D. while
【回答】
C
知识点：连词
题型：选择题
问题详情：
John waited at the bus-stop for nearly half an hour _____ the bus finally arrived .
A. when B. as C. before D. while
【回答】
C
知识点：连词
题型：选择题
