Do you have any doubt ------- a cure for AIDS will be found soon?

题目

Do you have any doubt ------- a cure for AIDS will be found soon?
that or if

答案

that
doubt vt.
怀疑; 不信; 拿不准(后接名词从句时,疑问句和否定句用连词 that,but,but that,肯定句一般用连接词 whether,if,what,when 等,如肯定句用 that,往往表示非常怀疑)