If students study hard for their math exam, they will pass. If someone has trouble seeing the blackboard, they need glasses. If a person sunbathes every day during the summer, they will get a tan by the end. If someone attends a birthday party, they should bring a present. If a woman sees a snake, she will shout loudly because she is afraid of snakes. There is a superstition that if you break a mirror you will have seven years of bad luck. You cannot legally drive a motorbike without a driving license. Drinking coffee in the evening will prevent sleeping. If teeth are not cleaned daily, cavities can develop.