Clear Contents of column based on data in another column

Hi Guys,

I need to clear the contents of a columns G and H starting 11th row based on what is there in F column. The macro should check for last non-empty cell in column F starting F11 (assume it finds F30 to be last non-empty cell), then it should clear the contents of G11 to G30, H11 to H30.

Any help please.

Taking above example, after G30, i.e. starting G31 all the cells will be protected (it's a dynamic protection). So, alternatively, if there is a way to write macro to clear content of all cells in column G starting G11 until it hits first protected cell, that will also work. I need not check in column F in that case.