ダース単位で卵を買う。

dozen

unit; denomination; credit (in school)

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.

eggs; egg; spawn; roe; hen egg; (an expert) in the making; beginning; origin; infancy

indicates direct object of action; indicates subject of causative expression; indicates an area traversed; indicates time (period) over which action takes place; indicates point of departure or separation of action; indicates object of desire, like, hate, etc.

to buy; to purchase; to value; to have a high opinion; to stir; to provoke