QUESTION: Fix punctuation: Oil has affected us humans in so many ways the last century
ANS: Oil has affected us humans in so many ways the last century.

QUESTION: Fix punctuation: This second paper on algebraic couples identified them with steps in time and he referred to the couples as time steps
ANS: This second paper on algebraic couples identified them with steps in time and he referred to the couples as 'time steps'.

QUESTION: Fix punctuation: At the bottom youll find a basic layer of ice painted white
ANS: At the bottom you'll find a basic layer of ice, painted white.

QUESTION: Fix punctuation: In the case that your MAPF file doesnt open it is highly likely that you do not have the correct software application installed on your PC to view or edit MAPF file extensions
ANS:
In the case that your MAPF file doesn't open, it is highly likely that you do not have the correct software application installed on your PC to view or edit MAPF file extensions.