I don't really see the problem. At least in the English language, the full stop (dot, '.'), exclamation mark '!', and question mark '?' indicates the end of a sentence, while a space indicates a separation between words. Therefore, having this text fragment "This is sentence one. And this is sentence 2" it is quiet obvious that the dot after the word "one" indicates a full stop and therefore the end of a sentence.
There are two types of vessels, submarines and targets.