I may guess Most of us don't get the point without context. And I guess the definition is"beat"? However,"打败”may not only mean beat someone phisically,it can also be mentally or "我被你打败了”could mean "Ok,you win ,I lose,I comprmise"to tell the other you don't intend to go any further about the problem. Let me know if you have other problems on this question :)

重复说一个事情 =Repeat a thing

很少这样说，不够简练，说话的人要突出这位老师的厉害 Rarely say so, not enough concise, the speaker should be highlighted the teacher

被我打败be defeated by me 把我打败to defeat me 句子中主要体现的不是打败的用法，而是被字句和把字句的用法

Dear Friend 打败 meas defeat. 我把你打败= I defeated you 我被你打败=I was defeated by you. Got it?