[COLOR="DarkRed"]Maybe, perhaps, possibly, probably[/COLOR]
[COLOR="Blue"]Do they mean the same thing and can be interchaged?[/COLOR]
1. Maybe it is going to rain.
2. Perhaps it will rain in one hour time because the sky is dark.
3. It is possibly to rain today because of the dark cloud in the sky.
4. Probably it will rain very soon because humidity is high. :D