Something unexpected happened, but it was a pleasant journey.
A. in detail
B. on average
C. to a degree
D. on the whole
网友回答
A. in detail
B. on average
C. to a degree
(答案→)D. on the whole
解析：考查固定词组，A. in detail详细说明；B. on average平均；C. to a degree在某种程度上；D. on the whole总的来说，句子意思“一些不希望的事发生了，但是总的来说旅行很愉快”