Form and rules
How it works
Use something/somebody/somewhere most often in ordinary positive statements.
Use anything/anybody/anywhere most often in questions and after a negative verb.
Use nothing/nobody/nowhere to give a negative meaning without another negative verb: I saw nobody.
Avoid double negatives in standard English: say I didn't see anybody, not I didn't see nobody.
Offers and requests often use some- words when the speaker expects or hopes for a positive answer: Would you like something to drink?