题目内容：

3.The old man was afraid _____ the bridge because he was afraid _____ into the river.
A.to cross; of falling
B.to cross; to fall
C.of crossing; to fall
D.of crossing; of falling

优质解答

选A
be afraid to do sth表示害怕去做某事,强调动作,在这里就是害怕“过桥”
be afraid of sth则表示对某事感到恐惧,即强调状态,此处就是害怕“掉进河里”这件事.