Use the AutoCorrect feature to remove line breaks that occur within sentences. Unwanted line breaks can occur when you copy text from another source and paste it into a text document.
This AutoCorrect feature only works on text that is formatted with the "Default" paragraph style.
Choose Tools - AutoCorrect - AutoCorrect Options.
On the Options tab, ensure that Combine single line paragraphs if length greater than 50% is selected. To change the minimum percentage for the line length, double-click the option in the list, and then enter a new percentage.
Click OK.
Select the text containing the line breaks that you want to remove.
In the Apply Style box on the Formatting bar, choose “Default”.
Choose Tools - AutoCorrect - Apply.