"Something" as it is written?

Particles are the service parts of speech that help express their emotions and attitude to what is being said. Particles are written with words separately, together and through a hyphen.

In this case, we want to learn how to spell "somethingthat. "The word" something "is a particle.The word" what "is a pronoun.So, a particle of" something "with pronouns (which, who, how, etc.) is written through a hyphen, so the correct version of writing: what.