How can I delete extra returns in my document?

Question

When working in Pages I will sometimes copy and paste from the internet. It will be single spaced lines. Then I will hit 'return' to say, begin a new paragraph, and it double spaces and leaves a one line space between the previous text and the new I type. I have tried making the entire document "Line Spacing - 1" but it still does it. Does anyone know how to adjust? For example:
Debriefing can serve as an opportunity to reflect on an experience and make it meaningful by identifying what we learned about ourselves and others. The technique of debriefing is useful for group members following the completion of an activity or event.
becomes
Debriefing can serve as an opportunity to reflect on an experience and make it meaningful by identifying what we learned about ourselves and others.
The technique of debriefing is useful for group members following the completion of an activity or event.

Answer 1

mel,
One way to approach the problem is with Find and Replace.  Start by Saving your document in case anything goes wrong.  Next,  View > Show Invisibles, if you don't already have invisibles showing. Then Command-F to bring up the Find and Replace window.
Next, click to set your insertion cursor right at the end of the sentence before the extra space in one of your blocks of text. Hold down the shift key while you click the RightArrow twice to Select the two "New Paragraph" markers.  Then, Command-C to copy them.
Set your insertion cursor in the Find field and Command-V.
Then set your insertion cursor in the Replace field and Command-B and delete one of the two characters.
Now, click Replace All.
Your extra lines should be gone.
Jerry