I can do it,do it,do it这首歌叫什么?

I can do it,do it,do it这首歌叫什么? I can do it I must do it !I can do it !I will do it !什么意思 I can do it myself.//什么意思? what do I can do it I can't do it ( ) Yes i can do it I can't do it What can i do it i can do it.这个do 做什么成分呢? I do it because I can do it,I can do it because I we can do it!I will do it !是什么意思?