This paper investigates the distribution of imperfective and perfective verb inflections in Kuwaiti Arabic. Spontaneous speech of three children (1 ; 8-3; 1) was analyzed for accuracy and error types. The results showed that the verbal inflections appeared correct almost all the time (89-97% of the time). Agreement errors appeared 3-11% of the time. The children did not inflect the verb in obligatory contexts in describing ongoing action 2-12% of the time. It is predicted that children acquiring Arabic would select a default form in place of fully inflected forms. The children used a non-finite form which is identical to the imperfective verbal bare stem to describe ongoing action, which is consistent with Benmamoun's argument (1999, 2000) that the imperfective bare verb is the default form in Arabic. The findings of the study are discussed in the light of the Optional Infinitive (OI) stage argued by Wexler (1994, 1996, 1998). The fact that the non-finite is non-tensed makes this type of behavior consistent with the OI.