This is the 784th most frequent Estonian word.
andsid
"Andsid" means "gave" in English.
This sentence uses 'andsid' in an interrogative structure to ask about the doers of the action in the past.
Kes andsid sulle selle idee?
Who gave you this idea?
Here, 'andsid' is in the past tense and second person singular, indicating the action performed by 'you'.
Sa andsid mulle raamatu tagasi.
You gave me the book back.
In this context, 'andsid' is used in formal speech or addressing a group in the past tense.