xsv slice -s 2 -e 4 data.csv

The slice command extracts a contiguous range of rows by 0-based index: -s 2 starts at the third row and -e 4 stops before the fifth, so rows 2 and 3 are printed. This is the CSV-aware replacement for sed -n on tabular data. Without -e the slice runs to the end of the file. Negative indices count from the end.