"About to" ~락 말락 하다 & ~랑 말랑 하다 | Live Class Abridged

This Sunday I did a live stream all about the grammar form ~락 말락 하다, which is an advanced form. Where have you seen this form used before?

We also learned about the related form ~락 ~락, as well as ~랑 말랑 하다, and talked about its origins.