as (someone did something), (something happened)

Here's a rather formal way of describing two things that happened at the same time:

As I was waiting at the bus stop, a dark rain cloud blew in from the north.

A more casual way to describe the same situation would be:

I was waiting at the bus stop when I saw a dark rain cloud coming my way.

"As I ___, ___" is more common in written stories than in stories told out loud.

This phrase appears in these lessons: