Automobile

Presumably it's a 2 stroke engine and that's the easiest way to lubricate the big end, little end and bore.

On a 4 stroke the underside of the piston is force/splash lubricated as it is all exposed to the sump. On a 2 stroke the volume under the piston is enclosed as it acts as the intake volume for the fuel/air mixture before transferring it to the volume above the piston at the lower portion of the stroke.
Some two strokes do have forced lubrication but adding oil to the fuel is still a common way of lubricating.

Some of this oil gets burnt of course which is why 2strokes produce more smoke/pollution/characteristic small that a 4 stroke...

Del

So the oil in the fuel doesn't lube the crank/connecting rod bearing, yes/no?

I said "Presumably it's a 2 stroke engine and that's the easiest way to lubricate the big end, little end and bore."

The 'big end 'is the 'crank/connecting rod bearing' ... so that would be a 'yes'

The 'big end' is the 'big end of the con-rod' ...
The 'little end' is ...yes you've guessed... the 'little end of the con rod'

Or aren't these expressions used in the US?

Del

Or aren't these expressions used in the US?

Yes in vertical orientation