Hello, Yunjiang.
There is additional information at the RepeatMasker site at http://repeatmasker.org/webrepeatmaskerhelp.html#reading. The main RepeatMasker documentation page is at http://repeatmasker.org/webrepeatmaskerhelp.html. If you still have question, you may also want to consider contacting RepeatMasker at http://repeatmasker.org/cgi-bin/form2mail?template=feedback.tmpl&title=Feedback Form.
Please contact us again at gen...@soe.ucsc.edu if you have any further questions. All messages sent to that address are archived on a publicly-accessible Google Groups forum. If your question includes sensitive data, you may send it instead to genom...@soe.ucsc.edu.
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Steve Heitner
UCSC Genome Bioinformatics Group
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