问题补充：
If it sunny tomorrow, I the Great Wall.
A. will be, climb
B. is, climbing
C. will, am climbing
D. is, am going to climb
答案：
A. will be, climb
B. is, climbing
C. will, am climbing
(答案→)D. is, am going to climb
解析：句意：如果明天天气好，我将去爬长城。if引导的条件状语从句，主句用将来时，从句用一般现在时表将来，故选D.
