It can be that you have a quite a lot of text in a property value field (or a description field) and that you want add some line breaks (‘enters’) in the text.
This can be done by using the key combination Shift-ENTER.
The need for line breaks can be an indication of long requirement texts. Ideally, long texts are avoided because they tend to include multiple requirements (so-called ‘compound requirements’). For the purpose of verification, it is best to break up such texts into smaller (individually verifiable) properties and/or relations.