This paper examines the nature of finite and nonfinite main declarative sentences produced by L2 child learners. It claims that two of the main proposals on the root infinitive (RI) phenomenon, the Truncation Hypothesis (TH) and the Missing Surface Inflection Hypothesis (MSIH), are not mutually exclusive in child SLA because they are hypotheses on completely different issues. According to the TH, different roots are involved: RIs are VPs underlyingly, whereas finite clauses are IPs or CPs. The MSIH claims that L2 learners have difficulties using the exact inflectional morphology, which leads them to produce verbs with an infinitival marker or no inflection at all. These so-called default forms are finite. In principle, then, an L2 learner could project truncated structure and produce default finite forms at the same time. This possibility is investigated in longitudinal data from an English-speaking child learning German. Two complementary sets of data can be accounted for by the hypotheses. Verbs bearing a nonfinite marker are restricted to nonfinite positions, which is consistent with the TH. Bare (uninflected) forms occur in the same (finite) positions as verbs inflected for person and number, which suggests that they are finite. This finding is consistent with the MSIH.