With Dependencies feature, you can make fields emerge based on the choice of a certain conditional field. To add a Dependancy, you need at least one conditional field and another one that has to appear when a choice is made. You can add Dependencies while creating a new Library, or while Editing an existing one:

• Add a field that you want to make dependent on another field, or edit an existing field.
• Choose Dependencies option, then click on Add dependency. By now, you should have a conditional field in this Library that you want to set the dependency.
• Check the Type, and set the field that you get the dependency From. Once you choose the second option, you can set the condition when this field is showing up during the entry adding process. The options will differ based on the type of field you set the dependency From.

For example, you have a Library with the video games impressions, and the conditional field is “Would you recommend this game?“. It is a Boolean type field, so the dependent field can be shown under one of two conditions: Checked, or Unchecked. I will choose Checked if the dependent field will describe the positive impression, and Unchecked if I wish to explain why should nobody ever play this game again.

Make sure to Save the changes, and you are good to go.