1. A semantic answering system that returns natural language answers in an S-A-O (subject-action-object) format in response to a natural language question, wherein the S-A-O format represents semantic relationships between the S, A, and O elements, the system comprising: a problem statement generator that processes the natural language question to extract a problem statement in a format X-A-O, S-A-X, S-X-O, or S-X-X, wherein S, A, and O are semantic elements in the natural language question, X indicates absence of an S, A, or O; a knowledge base comprising an answer database including a set of answer S-A-Os and, for each answer S-A-O, a link to a source document; a semantic server configured to perform a non-keyword query of the knowledge base using the semantic elements and semantic relationships from the problem statement to find at least one answer S-A-O, wherein the at least one answer S-A-O includes the A and O, S and A, S and O, or S from the problem statement and an S, A, or O to replace each X in the problem statement, thereby completing the S-A-O format; and a communication device configured to output the at least one answer S-A-O to a computer.