Question

①I found really hard for them to climb such a high mountain.

   A. this   B. it   C. that   D. one

Answer 1

①B 考査it作形式宾语。句意：我发现对他们来说登上如此高的一座山真困难。

it作形式宾语，真正的宾语为其后的动词不 定式。