i have learned that we cant use it or not in one sentence...<br/><br/>for example, I don't know if or not he is coming...<br/><br/>but i dont know if he is coming or not... this sentence is possible to use..<br/><br/>One of my friends told me that it's possible to use ' if or not' ...<br/><br/>anybody knows?? any examples??? <img class='emoticon' style='Width:19px;Height:19px;' data-delaysrc='https://uat-englishforward-forums-backend.s3.us-west-2.amazonaws.com/Emoticons/9.gif' src='https://uat-englishforward-forums-backend.s3.us-west-2.amazonaws.com/Emoticons/9.gif' alt='Emotion: crying'/>