问题
选择题
Some scientists believe that is no doubt a cure for AIDS will be found.
A．it; that
B．it; whether
C．there; that
D．there; whether
答案
答案：C
句意：科学家相信，毫无疑问，艾滋病的治疗方案终将被找到。Believe后面的that引导宾语从句，在从句中第一空用it做形式主语，that引导真正的主语。