9. When I first arrived in Japan, I was surprised ------ the

When I first arrived in Japan,I was surprised ____D__ the way people greeted each other.
A of B to C with D at
be surprised at 对...惊讶
再问： 其他三个选项 怎么不选 to和 with 呢
再答： be surprised at sth对某事感到惊讶，是固定搭配 如果接to ,那么后面不能接sth,能接动词原形do be surprised to do 表示做某事很吃惊；惊讶做某事；对做某事感到吃惊