The Gravity Forms List field lets members enter several rows of information (with optional columns and dropdowns) in one tidy field, instead of filling in many separate boxes.
Add a List Field
Go to Content > Gravity Forms and open your form from the Forms tab.
Click Advanced in the field list, then click List.
Set Up Columns
Click enable multiple columns if you need more than one column.
Click apply dropdown on any column that should be a dropdown.
Enter your column names and dropdown choices.
Result
Your form now shows a row with multiple columns and dropdowns.
Members click the plus sign to add another row.