They repeated the experiment several times ______ they were sure that the result was reliable.

admin2014-02-19 29

问题 They repeated the experiment several times ______ they were sure that the result was reliable.

选项 A、until
B、for
C、since
D、when

答案A

解析 until引导时间状语从句，表示动作持续到某一时间点。其他选项不合题意。例如：He waited for his friend at the bus stop until the last bus came．(他在车站等他的朋友，一直等到最后一班车来。)

转载请注明原文地址:https://kaotiyun.com/show/KygK777K

大学英语三级B级

相关试题推荐

随机试题

最新回复(0)