How would I remove entire words from a string that contain characters that are not from the alphabet?

**Edit** However, `'` and `-` should be the only characters that are allowed alongside the alphabet.

E.g: `This is a? #test e3ample`

Becomes: `This is`

The solutions I have found are focused on removing specific characters from a string rather than the whole word.

I have tried creating an array with banned characters but that is bad practice. How would I do so with Regex? Or something similar.