How are ad groups structured?

Start by going through each ad group and keeping an organized list in an Excel document. Then use either Google’s Keyword Planner or WordStream’s Keyword Tool to find relevant keywords for each ad group. Be sure to keep in mind that it’s best to start small with the number of keywords you use per ad group (10-20 max).

For More Information Please Refer: https://www.wordstream.com/blog/ws/2015/03/06/adwords-account-structure