Complex sentence: If proteins were layered on the surface of the membrane, their hydrophobic parts would be in an aqueous environment also it would separate the phospholipid heads (hydrophillic) from the water.
Split into simpler sentences: If proteins were layered on the surface of the membrane, their hydrophobic parts would be in an aqueous environment. Also it would separate the phospholipid heads (hydrophillic) from the water.