-lisha

What are now vowel-final verb stems originally had an -l-, which resurfaces whenever a suffix is added. The rule was then extended to borrowed words by analogy.

-lisha (mid vowel harmony variant -lesha)

1. Alternative form of -isha used in verbs ending in -aa, -au, -oa, -ua, or -uu, and in dysillabic verbs ending in -ia

   ‎-vaa (“to wear”) + ‎-lisha → ‎-valisha (“to dress”)

   ‎-sahau (“to forget”) + ‎-lisha → ‎-sahaulisha (“to cause to forget”)

   ‎-toboa (“to reveal”) + ‎lesha → ‎-tobolesha (“to cause to reveal”)

   ‎-tia (“to put”) + ‎-lisha → ‎-tilisha (“to cause to put”)

• Swahili causative verbs