§5.4 and §5.5 do NOT require you to remove brackets and write formulas shorter. To keep up with your skill in removing brackets, try to regularly make some exercises from tinyurl.com/removing brackets:

lvl 3, 4 and 5: single brackets (§5.1)

lvl 6, 7 and 8: double brackets (§5.2)

lvl 9: writing formulas with not only brackets shorter (§5.3)