我们在走廊里进行了一次随意的会面。

We had a ___casual meeting in the hallway.

她关于天气的随口一说引发了一次更长的聊天。

Her ___casual remark about the weather started a longer chat.

是一次随意的交谈促成了我们的商业合作。

It was a ___casual conversation that led to our business partnership.