记住(jì zhù) - remember, commit to memory in Mandarin

记住 means 'to remember firmly': 记 (jì, 'to note', with 讠the speech radical) plus 住 (zhù, 'to stay, to hold fast'), used here as a resultative complement meaning the noting 'sticks'.

Origin

compound

Root

记 (jì, to note) + 住 (zhù, to hold fast, resultative)