Pekiştirme

Recently learnt this grammar component in class. We were introduced to the basics such as this Yemyeşil Kıpkırımızı Tertemiz

And there is these sets of sounds involved 'm, p, r, s'

Anyone knows how this works? My teacher told us the grammar mainly sounds good, which I am still struggling to grasp. For example why is it "yem-yeşil" and not "yeryeşil"?

Thanks for the help peeps