1.Water is cheaper than meat. (MORE) 
----> Meat is more expensive than water.
2.She is not taller than anyone in her class. (SHORTEST) 
----> She is the shortest one in my class.
3.No one in my team works seriously than Peter. (MOST) 
----> Peter is the most serious one in my team
4.My mother is not as fat as my father. (FATTER)
-----> My father is fatter than my mother./ My mother is fatter than my father.