Adding Columns on a shared sheet

edited 12/09/19 in Smartsheet Basics

Good morning,

I am sure this is an easy one, but I cannot find an answer or explain why it is happening! 

I am unable to add any columns to any sheets that have been shared to me. I can however add columns to my own sheets without any issues. Is there a special way to share a sheet so that the sharee has the same ability to modify the sheet that the sharer?