Twitter Bounding - How to distinguish among more than one bounding box coordinates?

First, thank you for adding "location" featuring bounding box for Twitter. As per the description --

A comma-separated list of longitude, latitude pairs specifying a set of bounding boxes to filter tweets by. See https://dev.twitter.com/streaming/overview/request-parameters#locations for more details.

How to distinguish between more than one bounding box coordinates? Usually, for one bounding box they are comma separated. How to specific the next bounding box then?

thank you.

There's an example of this in the Twitter documentation:

-122.75,36.8,-121.75,37.8,-74,40,-73,41 San Francisco OR New York City