巩固
gǒng gù · HSK 6
to consolidate
🧱 巩 (consolidate) + 固 (solid/firm) = make solid through and through
巩 on its own means to secure or consolidate; 固 means solid, firm, or stubborn. Stacking two near-synonyms doubles the force — used for cementing knowledge, alliances, or a regime's power.