What is different between "What did you see there" and "What have you seen there", thanks.
If you mean in English? There's pretty much no difference, although "what did you see there" implies that you were there once. "What have you seen there?" implies that you went there many times. But really you can use either - "What did you see there?" is more normal
Actually "see" it is a present simple . In the past simple actually we use the "saw" . When we use the Past Simple, we use time phrases to say when the action took place. Time phrases include words and phrases like "yesterday", "last year" Of course you would not say : I eat soup yeasterday? no ofc . That is why you need to say that in the "past simple form". It means "saw".not see ! https://www.universitybridgeproject.org/past-simple/
This is a question. "What did you see?". The past tense is conveyed in the word "did", not "see".
Please don't act so confident, phrase your comment as a question about something you don't understand :)