The actual text will be 132 characters wide, so it would be prudent to make your window at least this width before editing the file. This will happen often with contractions due to an artifact of automatic alignment. The basic criteria for correctness is whether the normalized text is what you want for building a language model. The former token is the word I , and the latter is used to spell out letter sequences containing the letter I . Any punctuation in the normalized text is wrong unless spelled out as a word.
Misspellings are errors.