Long description layer in legend of ArcGIS for Desktop? [duplicate]

This question already has an answer here:

• How to allow for multiple lines in legend? 1 answer

I work with arcview 10.3 and i have layer with long description (green),hence the legend spread throw out the map:

I have to use a singel symbol for the layer

and not use the unique value as describe in How to allow for multiple lines in legend?

I wonder if there a way to shorten the description line by sliding the line into another line under ?