Questions & Answers about Он говорит чушь.
Говорит is the 3rd person singular present tense form of говорить.
- говорить = to speak, to say
- он = he
- so он говорит = he speaks / he is saying
There is no -ся here because the verb is not reflexive. Говориться is a different verb and would not be used in this sentence.
This is mainly about aspect.
- говорить is imperfective
- сказать is perfective
In a sentence like Он говорит чушь, Russian presents the action as something ongoing, repeated, or simply as a general fact: He is talking nonsense / He says nonsense.
If you used сказать, you would usually be talking about one completed act of saying something:
- Он сказал чушь = He said nonsense / He said something stupid
So говорит fits better for he’s talking nonsense or he speaks nonsense.