Predictions were formulated for extended Optional Infinitives (OIs) stage in German-speaking children with specific language impairment and evaluated in clinical sample of 8 SLI German-speaking children, ages 4; 0 to 4; 8; and control group of 8 younger utterance-equivalent children, ages 2; 1 to 2; 7. Samples reveal that affected group more likely than younger control group to use infinitive lexical verbs in declarative sentences. (Author/JL)