アップルパイを焼いたの。

apple pie

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 burn; to roast; to broil; to grill; to bake; to toast; to barbecue; to heat; to heat up; to make (charcoal, pottery, bricks, etc.); to bake; to fire; to burn; to tan (i.e. suntan); to burn; to print (a photo); to burn (an optical disc); to be jealous of; to be envious of; to envy

indicates possessive; nominalizes verbs and adjectives; substitutes for "ga" in subordinate phrases; (at sentence-end, falling tone) indicates a confident conclusion; (at sentence-end) indicates emotional emphasis; (at sentence-end, rising tone) indicates question