Thank you Mr.Steve!!

When thinking with%, it is a little easier to understand because I put in a sentence because I have to think "Well" to talk and write again.

But I still have to think while thinking, but I will consider another example sentence even by myself. It was sunny that I was somewhat unpleasant.

Probably, likely, perhaps, maybe and possibly translate to Japanese as "たぶん" or "おそらく". I understood a little bit.

かれいさん、面白いです！私は「多分」が分りません。I think CountOfDarkness's answers are good. I would say:

probably = 80~99%　certain

likely - the clouds are dark tonight, so it is likely it will rain.

perhaps and maybe = 40~60% sure

possibly = 考慮中です. If I buy a lottery ticket, I will possibly win.

本当に、「多分」が難しでよ！ When someone says 多分, it might mean that there is a strong likelihood. But it might also mean that I am trying to ignore your request.

Thank you  for telling me!! I will practice them.

I am not a native English speaker, but I would describe it in a such way:

Probably - I am shure at 80%.

Likely - I am shure at more than 50%

Maybe - I am not shure, but such possibility exists.

Perhaps - I have a suggestion.