地震が起こったら私達はどんなことになるだろうか。

earthquake

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

to occur; to happen

we; us

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

what; what kind of; (with -temo, demo, etc.) any(body, thing, means, etc.)

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

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 become; to get; to grow; to be; to reach; to attain; to result in; to prove to be; to consist of; to be composed of; to succeed; to be complete; to change into; to be exchanged for; to play a role; to be promoted; to do ...

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

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