To help you spot instances where adgroups do not have any active keywords (excluding DSA adgroups), Adalysis will regularly analyze your account and alert you whenever it identifies such cases (you will see the alert on your Dashboard, under Audit Alerts / Keywords):

You can take the recommended action without leaving the Dashboard by clicking on the button Pause affected adgroups. If, instead, you want to see the adgroups first and then decide how to best solve the issue, click on View affected adgroups and do the following. 

Step 1

Clicking on the above alert will open the Adgroups screen showing such adgroups:

Step 2

You can either pause these adgroups one by one, or in bulk:

or go through each one of them (click on adgroup name) to see the existing ads or paused keywords. Use the navigation to iterate through all the adgroups. You can see the paused keywords (or no keywords) in each adgroup.