单选题 It's not enough ______ that you love someone; you must show them.
A. saying B. said
C. to say D. to saying

【正确答案】 C
【答案解析】[解析] it是形式主语，空格之后是句子的真正主语，形容词enough和带to不定式一起构成be enough to do(做……很充分，足够……)的形式。