Ẹ kú, O kú, or A kú of the Yorùbá Language parlance has a great linguistic value as it is being
used in a myriad of morphosemantic structures. The adjectival modifier bon of the French
Language is equally well noted in its morphosyntactic and semantic usage structures. The major
challenges encountered by learners are the usage of these idiomatic expressions, especially those
characterized by polysemic adjectives such as “bon” in the studies of French Language and Ẹ kú
of Yorùbá. These expressions, splendid in cultural meaning and often far from their literal
meaning, pose interpretation problems and incorrect usage among learners. This study identifies
these difficulties and proposes solutions to them. A contrastive language elements usage of Ẹ kú
in Yorùbá and that of bon in French demands an in-depth study of their relativity in considering
the morphosemantic structures of the two elements: Ẹ kú of Yorùbá and bon of French. Having
explored the theoretical framework on the intersection of cognitive linguistics, pragmatics, and
didactics of language, as well as the descriptive qualitative approach, we found that French and
Yorùbá have some common grounds in their morphosyntactic varieties of words used in greetings,
compliments, socio-cultural situations, and acknowledgements. We therefore recommend that
learners or linguistic researchers be more prominent in finding out the relativities of the spoken
and written forms of the languages of their research in order to enhance their linguistic capacities.