Last week we talked about punctuating basic dialogue. The first rule is that punctuation almost always goes inside the quote marks--we'll get to the exceptions later. Let's take it one step further today, and split the dialogue before and after a dialogue tag (he said, asked John, etc.).
The important thing to remember is to punctuate the spoken words as you would any other sentence. The dialogue tag in the middle needs to be separated from these words by commas and quote marks.
"I think," said Jack, "you're making a mountain out of a molehill." Note the commas after think and Jack, the lower case letters at the beginning of said and you're. Also note quote marks after think, and before you're. There is a space between the quotes and the tag. I've marked the spaces in red to make it clear.
Here's another example. "Carol," he asked, "are you sure?" Again, there is a comma at the end of the first part of the dialogue and at the end of the tag. The first letter of the tag and the first letter of the second part of the dialogue are lower case (unless either one begins a name). Most especially, note that the question mark comes at the end of the sentence and inside the quote marks.
Naturally, there are exceptions and variations. Be guided by how you want the reader to "hear" the dialogue. If you read the first example aloud, notice that you slow down a bit when you come to the tag. This suggests to the reader that Jack is speaking slowly, perhaps with an emphasis on I to differentiate his opinion from someone else's, or that he's not entirely sure of what he's saying.
Let's try something a bit more advanced. It's not really complicated if you remember that you are punctuating sentences.
"I'll remember that," said Jack. "Punctuation is really complicated." Here the dialogue consists of two sentences: I'll remember that. Punctuation is really complicated. So you put a period after Jack. Many writers think that if dialogue continues, the tag is always followed by a comma. Not true. If the dialogue consists of two or more sentences, put a period after the tag.
One last consideration today. The rules about question marks and exclamation marks we learned last week also apply to split dialogue.
"I'll remember that!" said Jack. "It's complicated."
"Can you remember that?" the teacher asked. "It's not that hard."
Homework: if you have an example of split dialogue that puzzles you, ask me.