How to use cell fracture add-on to break only part of the mesh? When applying cell fracture add-on, the whole object is broken into small pieces. If I would like to keep part of the mesh to be unbroken (remain a big piece of object), how can I do that? Or do I need to use other things beside cell fracture to finish the job?

Thanks in advance.
You can use Bisect followed by V (not sure what the function is called but it duplicates the vertices selected effectively creating loose parts). The use Fill then Separate to split your object by loose parts then apply the cell fracture on the piece you want.