My wordpress really slow!!

start with a test
http://www.webpagetest.org/
see what basic issues are identified.
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next try some of these things
check plugins for high resource usage
https://ww.wp.xz.cn/plugins/p3-profiler/

check images that are high resolution/large size
try to change to a theme like twentytwelve to see if your theme is causing slowness
ask your webhosting company if there anything the can identify from the server side