彼は筆で生計を立てている。

he; him; his; boyfriend

topic marker particle; indicates contrast with another option (stated or unstated); adds emphasis

writing brush

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.

livelihood; living

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 stand up; to put up; to set up; to erect; to raise; to thrust into; to bury into; to dig into; to make (a noise); to start (a rumour); to raise (a cloud of dust, etc.); to cause; to make; to establish; to set up; to develop; to formulate; to put up (a political candidate); to make (one's leader); to treat with respect; to give (someone) their due; to make (someone) look good; to avoid embarrassing (someone); to sharpen; to make clear; to shut; to close; to make tea (macha); to perform the tea ceremony; to divide by; to do ... vigorously