Afro-Asiatic root-and-pattern system

ȡa;k-t-b 'write' (Arabic) katb-un 'act of writing'

katab-a 'he corresponded (with)' yu-katib-u 'he is in correspondence'

be;a-ktaba 'he has made (somebody) write' mu-katib-un 'the corresponding one'

yu-ktib-u 'he is making (somebody) write' katib-un, pl. kuttab 'someone writing, scribe'

mu-ktib-un 'making (somebody) write' kitab-un, pl. kutub 'book'

ma-ktab-un 'the place to write, school' ma-ktub-un 'written'