The Axis are Germany, Italy, Japan, and their allies.
The Allies are USA, Britain, France, and anyone who was not neutral and not with Hitler and the Nazis.
A point of order: any country claiming neutrality would not be considered an Ally. Even when the United States was still considered 'isolationist', the government was instituting 'Cash & Carry' & 'Lend-Lease' programs.
That isn't to say that Neutral countries weren't attacked or invaded (i.e. Norway, Holland & Belgium).
Axis
Because the Axis don't like the Allies so they battled it out
They were on the allies.
The axis.
Axis
Japan was an Axis power
The allies wanted an unconditional surrender from the axis.
You momma made up the axis and allies
USA was on the Allies.
The side of the Allies .
He was on the allies side.
Belonged to the Allies.