word/sentence alignment for English document

Question

I have a English document, which is preprocessed into two versions. I want to align words or sentences from these two versions of document. A simple example is as below:

I don't want to go there. My e-mail address ok.

should be aligned with

i do n't want to go there my e mail address ok

Or the tokens from the first sentence is aligned correctly with the tokens in the 2nd sentence. I have tried some sequence alignment methods, which do not perform well. Considering there are alignment tools for machine translation, automatic alignment for English should be easier right?