What do meters and liters and kilograms measure in nature?

Answer 1

Those things don't measure anything. They're the units you use

to tell others about your findings after you measure things.

Meters are used to report the length of something, like a piece of rope,

or the distance between two places, like the floor and the ceiling.

Liters are used to report the size of a region of space, and how much

it will hold, like a beer bottle or a super-tanker.

Kilograms are used to report the amount of 'stuff' something is made of.

That tells you and your listeners how much the thing will weigh on earth,

on any other body in the universe, or on the way from one to the other,

as well as how hard you'll have to push it in order to get it going, or to

stop it once it's going.

Answer 2

Meters measure distance or length, liters measure volume or capacity, and kilograms measure mass or weight in the natural world.