The assertions identify the primary and secondary clusters or categorisations of metacognition as discussed by Brown:
8.26 Knowledge of cognition is a form of self-awareness about one’s cognitions. It is the primary ‘cluster’ or categorisation of metacognition.
8.27 Regulation of cognition is the monitoring and control of one’s cognitive processes. It is the secondary ‘cluster’ or categorisation of metacognition.
See other related assertions on page 136-138 in the book The Taxonomy of Metacognition.