So, as @exchemist said on another thread, the -eth ending no longer used in Modern English is the third person ending for verbs (he speaketh).
But this is just one side of the story.
-eth was indeed the preferred ending for such verbs in many parts of Southern England; however in the North of England the ending -es was preferred (in other words, basically the way we tend to use it today; he speaks), but often with an extra 'e' - he speakes. Early on this 'e' would have been sounded.
The present participle, -ing, was also different, and in the majority of cases was not -ing but -and,
I'll let the book do the talking:
But this is just one side of the story.
-eth was indeed the preferred ending for such verbs in many parts of Southern England; however in the North of England the ending -es was preferred (in other words, basically the way we tend to use it today; he speaks), but often with an extra 'e' - he speakes. Early on this 'e' would have been sounded.
The present participle, -ing, was also different, and in the majority of cases was not -ing but -and,
I'll let the book do the talking: