If "funny" means humorous:
* Serious
* Solemn
* Dull
* Boring
* Uninteresting
If "funny" means strange or odd:
* Normal
* Typical
* Ordinary
* Expected
If "funny" means peculiar or unusual:
* Common
* Standard
* Conventional
* Traditional
If "funny" means comical:
* Tragic
* Serious
* Sombre
It's important to consider the specific meaning of "funny" in the context to choose the most appropriate antonym.