1．(2011·江苏高考)It was never clear ________ the man hadn't reported the accident sooner.
A. that
B. how
C. when
D. why
解析：句意：这名男子没有早点报告这次事故的原因根本没有搞清楚。it在句中是形式主语，真正的主语是why引导的主语从句。
答案：D
2．(2011·北京高考)________ Barbara Jones offers to her fans is honesty and happiness.
A. Which
B. What
C. That
D. Whom
解析：句意：“巴巴拉·琼斯给予她粉丝的是诚实和快乐。”“________Barbara Jones offers to her fans”在句中作主语，为主语从句。what引导主语从句并且在从句中作offers的宾语，故选B项。which表示“哪一个”；whom表示“谁”。均不符合句意。
答案：B
