Involvement can be in some (bus ambushes).Logical formLearned from13 sentences. A bus can be armor-plated against gunfire.Logical formLearned from13 sentences. A bomb may stop a bus.Logical formLearned from13 sentences. (Ambush bus) may carry tourists.Logical formLearned from13 sentences. Bus can be between some countries.Logical formLearned from13 sentences. Buses may return to streets.Logical formLearned from13 sentences. A father may become a (bus conductor).Logical formLearned from13 sentences. A bus may originated in a US-city.Logical formLearned from13 sentences. A (passenger bus) may crash.Logical formLearned from13 sentences. Signs can be on buses.Logical formLearned from13 sentences. Buses may be grounded to a halt.Logical formLearned from13 sentences. A bus may be owned by a company.Logical formLearned from13 sentences. An attack can be on a (passenger bus).Logical formLearned from13 sentences. Protests can be against (bus fare hikes).Logical formLearned from13 sentences. A (passenger bus) can be in a world-city.Logical formLearned from13 sentences.