そうだ

そうだ has two main uses: (1) hearsay: you convey information you heard from someone else. You attach it to the plain form of the clauses, and it expresses that what you’re saying comes from someone else’s report. (2) appearance/it seems: based on what you observe, you infer that something seems a certain way. In this sense, そうだ follows the plain form of adjectives or verbs before it, not after quotes. In everyday speech, そうだ often means you’re passing along information rather than making a personal judgment. When you want to state that you heard something from someone, you use the pattern Xだそうだ or Xだと聞いた notated as Xだそうだ after a noun or sentence.)