Can't insert and delete rows and columns in Excel 2013

I can't delete or insert rows or columns in Excel. Insert and delete is not available in the drop down menu and the Excel-sheet is not protected. I haven't disabled it and even though i create a new and blank sheet the options are disabled.

How can I enable it? Why does this happen?

Hi. Funny, I never use the menus to insert or delete.

I select the row or column, and then right click... the option to insert or delete is available.

Sorry for beeing unclear. I also use right click. But the options are not highlighted..

Thanks Richard!

It resolved my issue