Opportunity may knock at a door.Logical formLearned from12 sentences. Men may knock at a door.Logical formLearned from12 sentences. A ball may be knocked.Logical formLearned from12 sentences. A person may knock somebody.Logical formLearned from12 sentences. A person may knock persons.Logical formLearned from12 sentences. A deckhand may be knocked.Logical formLearned from12 sentences. A person may knock at a door.Logical formLearned from12 sentences. Officers may knock.Logical formLearned from12 sentences. Big waves may knock persons off jetties.Logical formLearned from12 sentences. A (ground engineer) may be knocked off feet by a force of a blast.Logical formLearned from12 sentences. A male may knock a shot.Logical formLearned from12 sentences. A male may knock a pass.Logical formLearned from12 sentences. Countries may knock on a door.Logical formLearned from12 sentences. Engine may knock.Logical formLearned from11 sentences. A woman may knock on a door.Logical formLearned from11 sentences.