斗胆发几首翻唱。。还有想要请教关于节奏的问题

married with children
http://www.tudou.com/programs/view/CCQFjUpMrjk/
stand by me
http://www.tudou.com/programs/view/bnBfD10qtGI/
wonderwall
http://www.tudou.com/programs/view/WCe2lxnLd3Y/
请问大家弹琴用什么方法掌控节奏，我发现我节奏很不稳，时快时慢。。。married with children用了节拍器，剩下两首没用，就悲剧了