彼らがなぜ私達にそんなにそんなに腹を立てているのかわからない。

they (usually male); them

indicates sentence subject (occasionally object); indicates possessive (esp. in literary expressions); but; however; still; and

why; how

we; us

at (place, time); in; on; during; to (direction, state); toward; into; for (purpose); because of (reason); for; with; by; from; as (i.e. in the role of); per; in; for; a (e.g. "once a month"); and; in addition to; if; although

so much; so; like that

abdomen; belly; stomach; womb; one's mind; one's real intentions; one's true motive; courage; nerve; willpower; generosity; magnanimity; feelings; emotions; wide middle part; bulging part; inside; interior; inner part; anti-node; counter for hard roe; counter for containers with bulging middles (pots, vases, etc.)

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

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

indicates a question (sometimes rhetorical); or; whether or not; some- (e.g. something, someone); indicates doubt, uncertainty, etc.; emphatic prefix; suffix forming adjectives or adverbs; in that way

to understand; to comprehend; to grasp; to see; to get; to follow; to become clear; to be known; to be discovered; to be realized; to be realised; to be found out