我今天下午出去购物时偶然遇到了马克。

I ___bumped ___into Mark when I was out shopping this afternoon.

当我在街上偶然遇到一个朋友时，我们停下来聊天。

When I ___bumped ___into a friend on the street, we stopped to chat.

偶然遇到多年未见的人总是一个愉快的惊喜。

It's always a pleasant surprise to ___bump ___into someone you haven't seen in years.