An (undersea surveillance system) can be passive.Logical formLearned from2 sentences. (Sonar techniques) can be passive.Logical formLearned from2 sentences. A (target detection) can be passive.Logical formLearned from2 sentences. Conveyors can be passive.Logical formLearned from2 sentences. Risks may be associated with passive smoking.Logical formLearned from2 sentences. (Entertainment consumers) can be passive.Logical formLearned from2 sentences. (Measurement programs) can be passive.Logical formLearned from2 sentences. (Microwave radiometer data) can be passive.Logical formLearned from2 sentences. Surroundings can be passive.Logical formLearned from2 sentences. Programmes can be passive.Logical formLearned from2 sentences. A duplication can be passive.Logical formLearned from2 sentences. A capacitor can be passive.Logical formLearned from2 sentences. A (soil pressure) can be passive.Logical formLearned from2 sentences. Fighters can be passive.Logical formLearned from2 sentences. Mixers can be passive.Logical formLearned from2 sentences.