In lahā fakhidhān, lahā functions as the preposed predicate and fakhidhān as the delayed subject. The dual nominative ends in -ān.
In kaʾannahumā bābā, kaʾanna is an inna-type particle, -humā its subject, and bābā its predicate, nominative by the dual alif. Munīfin is the genitive second member of an iḍāfah. The paired dual nouns formally support the two-sided visual simile.