On the training page (/resources/training), there is a typo:

This training by Katie Nickels and Adam Pennington of the ATT&CK team will help you learn how apply ATT&CK to improve your threat intelligence practices.

This should be changed to the following:

This training by Katie Nickels and Adam Pennington of the ATT&CK team will help you learn how to apply ATT&CK and improve your threat intelligence practices.