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letter

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.

express; special delivery

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 send (a thing); to dispatch; to despatch; to transmit; to take or escort (a person somewhere); to see off (a person); to bid farewell (to the departed); to bury; to spend (time); to live one's life; to pass (down the line); to affix okurigana

to give; to confer; to bestow; to kindly do for one; to oblige; to favour; to favor