I'm sure to do it myself

I'm sure to do it myself 请问 whenever I do anything,I tell myself to be sure and I wil i'm not sure whether he has ______ to do with it.A.anything I'm sure it's going to _____(rainy) I'm sure it's gong to _____( rainy ) I’m sure about it. ____ interesting work it is!I’m sure I can do it well.A.How She is sure to win.This is ( )I'm quite sure about.A.it B.so Did i do it to make myself feel better?为什么有两个助动词did,do? Rather than John do it,I'd prefer to do the job myself. I bilieve myself,just do it! I can do it myself.//什么意思?