First, we put a hairpin on the scale, and then see which number the pointer on the scale points to. Point to 2, it's 2 grams.
Then take a big bottle full of water and put it on the scale. Look, wow! It weighs 500 grams! !
Next, take another pot and weigh it on a bigger pot. Wow! It weighs one kilogram! ! !
Do you understand the weight of things at home?