the contesting states- two states or two conditions or two people etc opposing each other
the contracting states- two states or two conditions or two people etc concuring each other
depositary state is some kinda organisation to which multilateral treat is entrusted which means this organisation is responsibke to treat some countries or such kinda organisation
dependent state is the state government or organisation which depends on another country or organisation and do not have enough power to control everything (e.x Russia is federation it includes several countries in it and these countries is dependent to Russia)
my friends and I usually play on the playground during the break and
sometimes we buy some snacks from a vending machine.