Complex sentence: Miss Earth Botswana 2009, Tumisang Sebina, was unable to compete in the international pageant since she did not meet the 1.64m Miss Earth minimum height requirement forcing organisers to change the local pageant rules rejecting anyone below the required height to ensure that Botswana is represented internationally.
Split into simpler sentences: Miss Earth Botswana 2009, Tumisang Sebina, was unable to compete in the international pageant since she did not meet the Miss Earth minimum height requirement. This caused organisers to change the local pageant rules that exclude anyone below the required height, ensuring that Botswana would be represented internationally.