コップはミルクでいっぱいだ。

glass (i.e. drinking vessel); tumbler; cop (police officer)

topic marker particle; indicates contrast with another option (stated or unstated); adds emphasis

milk

indicates location of action; at; in; indicates time of action; indicates means of action; cause of effect; by; and then; so; indicates continuing action; indicates certainty, emphasis, etc.

amount necessary to fill a container (e.g. cupful, spoonful, etc.); drink (usu. alcoholic); full; one squid, octopus, crab, etc.; one boat; fully; to capacity; a lot; much; all of ...; the entire ...

be; is; indicates past or completed action; indicates light imperative