请问怎么选择? WHY？谢谢！
166. Eric might have come to school in time for the lecture _______. A. if he got up earlier B. unless he had got up earlier C. but he got up rather late D. but he had gotten up so late
选A。 if he got up earlier，如果他能早点起床的话。 Eric或者可以及时来到学校听讲，如果他能早点起床早的话。
问：He had no idea of how the climb would be ____he was half way up the mountain.
答：从逻辑意思上来看应该选B.因为只有实际爬了山才会知道爬山是什么感觉，如果选when，爬到一半还没感觉，就不符合逻辑了。详情>>
