A male may bound_up stairs.Logical formLearned from19 sentences. Stairs can be darkened.Logical formLearned from19 sentences. A person may go_down stairs.Logical formLearned from19 sentences. An elsewise may pertain-to a stair.Logical formLearned from19 sentences. A step can be on stairs.Logical formLearned from19 sentences. A male may appear at a top of stairs.Logical formLearned from19 sentences. A room can be at a top of stairs.Logical formLearned from19 sentences. A flight may pertain-to stairs.Logical formLearned from19 sentences. (Stone stairs) can be steep.Logical formLearned from19 sentences. A person may come_down stairs.Logical formLearned from19 sentences. Stairs can be in a home.Logical formLearned from19 sentences. Sides may pertain-to stairs.Logical formLearned from19 sentences. The right may pertain-to stairs.Logical formLearned from19 sentences. Stairs can be to a room.Logical formLearned from19 sentences. Stairs may collapse.Logical formLearned from19 sentences.