Question

boy in the trouble

You can’t imagine the difficulty he _____ onto the cliff and saving the boy in trouble. A．had to climb B．had climbed C．had climbing D．had on climbing

Answer 1

C 考查定语从句和非谓语动词。句意：你不能想象出他爬上悬崖就这个陷入困境的 男孩的困难。he had做后置定语修饰difficulty，现在分词作伴随状语表示正在进行的伴随性动作，和he是逻辑上的主谓关系。故选C。