They adorned the room with flowers.
Heya o hana de kazatta.
room; apartment; flat; pad; chamber; stable
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.
flower; blossom; bloom; petal; cherry blossom; beauty; blooming (esp. of cherry blossoms); ikebana; Japanese playing cards; beauty; (the) best
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.
to decorate; to ornament; to adorn