If your text is automatically hyphenated and certain hyphenated words look ugly, or if you want specific words never to be hyphenated you can switch off hyphenation for those words:
Choose LibreOfficeDev - PreferencesTools - Options - Languages and Locales - Writing Aids
Select a dictionary in the \<emph\>User-defined dictionary \</emph\>list, and then click \<emph\>Edit\</emph\>.
If the list is empty, click \<emph\>New\</emph\> to create a dictionary.
In the\<emph\> Word\</emph\> box, type the word you want to exclude from hyphenation, followed by an equal sign (=), for example, "pretentious=".
Click \<emph\>New\</emph\>, and then click \<emph\>Close\</emph\>.
To quickly exclude a word from hyphenation, select the word, choose \<emph\>Format - Character\</emph\>, click the \<emph\>Font \</emph\>tab, and select "None" in the \<emph\>Language \</emph\>box.
Some words contain special characters that LibreOfficeDev treats as a hyphen. If you do not want such words to be hyphenated, you can insert a special code that prevents hyphenation at the position where the special code is inserted. Proceed as follows:
Position the cursor at the place where no hyphenation should occur.
Choose .
The inserted formatting mark will be shown in gray. To remove it, simply place the cursor over the formatting mark and press the Del key.