彼らは核兵器のことを気にかけているようだ。

they (usually male); them

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

nuclear weapons

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

thing; matter; incident; occurrence; event; something serious; trouble; crisis; circumstances; situation; state of affairs; work; business; affair; after an inflectable word, creates a noun phrase indicating something the speaker does not feel close to; nominalizing suffix; pretending to ...; playing make-believe ...; alias; aka; nickname; alternative name; also known as

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.

spirit; mind; heart; nature; disposition; motivation; intention; mood; feelings; atmosphere; essence

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 hang (e.g. picture); to hoist (e.g. sail); to raise (e.g. flag); to sit; to take (time, money); to expend (money, time, etc.); to make (a call); to multiply; to secure (e.g. lock); to put on (glasses, etc.); to cover; to burden someone; to apply (insurance); to turn on (an engine, etc.); to set (a dial, an alarm clock, etc.); to put an effect (spell, anaesthetic, etc.) on; to hold an emotion for (pity, hope, etc.); to bind; to pour (or sprinkle, spray, etc.) onto; to argue (in court); to deliberate (in a meeting); to present (e.g. idea to a conference, etc.); to increase further; to catch (in a trap, etc.); to set atop; to erect (a makeshift building); to hold (a play, festival, etc.); to wager; to bet; to risk; to stake; to gamble; to be partway doing ...; to begin (but not complete) ...; to be about to ...; indicates (verb) is being directed to (someone)

appearing ...; looking ...; way to ...; method of ...ing; form; style; design; like; similar to; thing (thought or spoken)

be; is; indicates past or completed action; indicates light imperative