There isn't a simple way to have a field automatically expand in Browse Mode to accommodate extra text. There are a few different things you can do:
1) If you use sliding (Inspector / Position tab / Remove blank space by / Sliding up), then when you enter Preview Mode or print the layout, the extra space you see in Browse Mode will be eliminated.
2) Shrink the size of the font so extra text can fit.
3) Use Conditional Formatting to shrink the size of the text dynamically. What you can do here is set a calculation to detect how long the text is, and, if it's beyond a certain length (what will fit in the field), then make it smaller. For example:
Case ( Length ( fieldName ) > 30 )
might be your formula. Then you set the font size to the next size down.
Thank you! The first part worked greatly!