Reading through some comic books, comic strips, movie subtitles, and video game subtitles, I noticed some inconsistencies in regards to putting a comma after the introductory word of a sentence, especially when it begins with a conjunction. I have tried looking for an answer online, but it seems to be about 50-50 whether it is necessary or not. Take this dialogue for example: So when do we need to go? Well the movie doesn't start for another hour. Then we should leave pretty soon. But the theater is very close to here. And are we going to get dinner? First I need to find my keys. Next I need to find my coat. Now go find them and meet me outside. Perhaps not the most proper conversation between two people, but that's not the point. Which of these sentences needs (or at least should have) a comma after the first word? Are there any sentences here where it is correct to keep the comma omitted? Sorry if this was already answered in another thread. I tried searching for it before posting this and came up short. Thanks in advance.