英語を身につけるのは難しい。

English (language)

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.

body; oneself; one's place; one's position; main part; meat (as opposed to bone, skin, etc.); wood (as opposed to bark); blade (as opposed to its handle); container (as opposed to its lid)

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

to turn on; to switch on; to light up

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

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

difficult; hard; troublesome; complicated; serious (disease, problem, etc.); fussy; particular; fastidious; hard to please; displeased; gloomy; glum; sullen; serious (look); dirty; unclean; filthy; detestable; unpleasant; uncomfortable; creepy; spooky