I bet that you are happy! (95-100% certain) You are probably happy! (80-90% certain) Maybe you are happy! (40-60% certain) I doubt that you are happy! (0-10% certain) *What are your theories about the Nazca Lines? Try to use the expressions above in your discussions. For example, I am not sure what the Nazca lines were because I am not an expert in this field. Nevertheless, I have some theories. Maybe, they were from their religion and the symbols represented something. Some people say they come from aliens, but I doubt that it was aliens.