Do you know if the mass of a paper clip is measured in grams, liters, or meters? Is a water bottle measured in grams, liters, or meters?
Watch to find out!
milli = one thousandth
centi = one hundredth
deci = one tenth
meter gram liter
kilo = 1,000
8 mg = 8/1000 grams and 8 kg = 8,000 grams
5cm = 5/100 m and 5km = 5,000m
More good explanations and pictures can be found at Math Is Fun!
And this conversion table might also come in handy.