Answer:
The contextual words that prove that Sergei regretted his second wish are: "In his mind, he was less sure".
Explanation:
Sergei had a magic fish that would fulfill his three wishes. The first wish he used to cure a cancer that his sister had. The second wish, however, he used to fix a deficiency in the brain in a child who was the son of a woman he was in love with.
After the child was healed, the woman started a romance with another man and Sergei regretted having made the wish, although he does not admit it, the text of the context words that makes the reader make this conclusion, since the narration says that in Sergei's heart he does not regret the request, but "In his mind, he was less sure".
