The students didn ’ t manage to work out the problem ______ their teacher had ex

游客2024-01-14  64

问题 The students didn ’ t manage to work out the problem ______ their teacher had explained how.

选项 A、when
B、until
C、unless
D、as

答案 B

解析 固定句型用法题。not…until…表示“直到…才…”。
转载请注明原文地址:https://tihaiku.com/zcyy/3362105.html
最新回复(0)