there are 2 details which are not mentioned in the document.

1. number(0-9) is also the splitor of word, so word can only contained characters,a-z.
   such as A0B is 2 words.
2. Next line starts one new word, but not always starts one new sentence, such as
   this is one sentence, but
   is splited to 2 lines.

666,it's correct