问题补充：
He studied hard, the exam.
A. aim at passing
B. aiming passing
C. aiming at passing
D. aim to pass
答案：
A. aim at passing
B. aiming passing
(答案→)C. aiming at passing
D. aim to pass
解析：考查现在分词做状语，这里的aiming at （旨在），是现在分词做伴随状语，修饰前面的谓语studied的。也可改为He studied hard and aimed at passing the exam。 但这样aimed at就与前面的studied一起做并列谓语了。句意：他努力学习，目的是通过考试。选C。
