Lesson 1 : "Maybe this is too hard for you". At first glance, this can sound helpful. But it may be a subtle way of insulting someone. Why was it necessary to add "for you"? Such statements depend on your intention and on the way the listener will respond.
Lesson 2 : We are not allowed to do or say things to scare others. This includes giving people false information as a joke, such as telling them their house burnt down or that someone was in an accident.