As we know, there were not any punctuation marks in the original text, and yet modern convention requires some and in so doing raises some interesting questions.
Take John 3:16 for example. If a person's talking requires several paragraphs, modern conventions is to put a quotation mark at the beginning of each paragraph, but only one quotation mark is included, and that at the end of the last paragraph. In other words, all of the paragraphs except for the last one do not close with a quotation mark.
There is a subtle change from the NIV to the TNIV (simply as an illustration, not as a comment on the translations). The NIV does not include a closing quotation mark on John 3:15, and includes a starting quotation mark with John 3:16. In other words, Jesus is still talking. The TNIV, however, reverses this. It includes a closing quotation mark on John 3:15 and does not include a beginning quotation mark with John 3:16. In other words, Jesus is no longer speaking.
This is actually a somewhat difficult decision. The fact that it is John 3:16 just makes it more visible. Most commentary writers agree that John often moves Jesus' discussion from dialogue to monologue. Nicodemus is there in the first ten verses or so, and then apparently disappears. The patten occurs throughout the gospel. Of course, the real question is, What does that mean? For some, the monologue represents John's reflections on Jesus' words, helping us to see the fuller meaning of Jesus' words. For others, it means the monologue has less claim for authenticity, assuming that John's words are less authentic than Jesus'.
For an evangelical with a high view of Scripture, even if the words are John's inspired reflection on Jesus' teaching, they are still as authoritative. But of course it is certainly possible that Jesus himself moved from dialogue into monologue as a way to teach.
So where do you stand on this? How will you express it? It all depends on where you put the quotation marks.