【题目】I'd appreciate ________ if you could let me know in advance whether or not you will come.
A.it
B.you
C.one
D.this

【答案】A
【解析】句意：如果你提前让我知道你是否回来，我会很感激。I’d appreciate it if/when/that…是固定句式，appreciate后跟接if或when从句时，其后不直接跟if或when引导的从句，若语义上需要接这类从句，需借助it。故选A。