Use the partitive article to say that you are eating some of these items.

Je mange ________ poulet.

Je mange du poulet.

Je mange _____ crepes

Je mange des crêpes.

Use the partitive article to say that you are eating or drinking some of these items.

Je prends ____ lait

Je prends du lait.

je prends _____ jus

Je prends du jus.