javascript
const regex = /\b(\w+)\s+\1\b/gi;
const result = str.match(regex);
python
import re
pattern = re.compile(r'\b(\w+)\s+\1\b', re.IGNORECASE)
result = pattern.findall(text)
go
import "regexp"
re := regexp.MustCompile(`(?i)\b(\w+)\s+\1\b`)
result := re.FindAllString(text, -1)