One of the most common hurdles for students is distinguishing between "-고 있다" and "-아/어 있다" . While both can often be translated as "is doing" or "is in a state" in English, they describe very different aspects of an action. Today, let's break down these two forms to help you ace your TOPIK 1 exam and speak more naturally! 1. Action in Progress: -고 있다 Use "-고 있다" when an action is happening right now or is a continuous habit. It focuses on the "movement" or "activity