The famous rhetorician Albert Beveridge believed that "no oratorical phrase can be considered successful if it contains expressions such as "I may be wrong," or "in my humble opinion," or "as far as I can tell." Great orators are always so confident that the final part of their speech sounds like a compelling truth. They are 'experts in their field', and ordinary people are happy to listen to them. " Do you agree with this point of view? What if the speaker really has doubts about a particular issue? Why do people usually prefer to deal with confident speakers, leaders, lawyers and politicians? How can a speaker demonstrate confidence in his or her ideas, and what signs (other than the phrases above) indicate his doubts?