Office 2010 splitting cells

I am having trouble splitting a cell into 3 in my worksheet, I have search the help list and all the icons on the ribbon. I know it is there somewhere but I am losing patience.


Chiller no 1 Chiller no 2





I need to split these two cells into 3 for say next 5 rows then converted back to one cell per row

I am slowly learning to use Microsoft Office 2010 but still need lots of help

Maggi