A 考查宾语从句和定语从句。____ the little ____ I have been able to do has been of some use是一个宾语从句,从句不缺成分,用that引导,也可省略。____ I have been able to do是定语从句,先行词是the little,在定从中作do的宾语,用that引导。所以选A。
b. that i hope that后面是宾语从句(中间的东西下面讲)has been of some use. the little(that) i have been able to do 我希望, 我能够做到的那一点点, 会有些用。 little , only , the one ,the only one , first 等序数词。 有以上这些时,定语从句只用that ,不用which