What goes zzub zzub zzub?
A fly flying backwards!
Backwards Fly
Explanation
Explain Bear
Alright, listen up, buttercup. This joke is easy peasy. See, a fly makes a "zzub" sound, right? So, if it's flying backwards, it's still making that sound. It's funny 'cause it's unexpected and kinda dumb. I bet you have to ask your mom what 1+1 is.